diff --git a/packages/babel-parser/src/parser/statement.js b/packages/babel-parser/src/parser/statement.js
index b677bfd0c9..3e950d2657 100644
--- a/packages/babel-parser/src/parser/statement.js
+++ b/packages/babel-parser/src/parser/statement.js
@@ -20,6 +20,7 @@ import {
   SCOPE_OTHER,
   SCOPE_SIMPLE_CATCH,
   SCOPE_SUPER,
+  type BindingTypes,
 } from "../util/scopeflags";
 
 const loopLabel = { kind: "loop" },
@@ -1611,11 +1612,12 @@ export default class StatementParser extends ExpressionParser {
     node: N.Class,
     isStatement: boolean,
     optionalId: ?boolean,
+    bindingType: BindingTypes = BIND_CLASS,
   ): void {
     if (this.match(tt.name)) {
       node.id = this.parseIdentifier();
       if (isStatement) {
-        this.checkLVal(node.id, BIND_CLASS, undefined, "class name");
+        this.checkLVal(node.id, bindingType, undefined, "class name");
       }
     } else {
       if (optionalId || !isStatement) {
diff --git a/packages/babel-parser/src/plugins/typescript/index.js b/packages/babel-parser/src/plugins/typescript/index.js
index 078797d74b..5d6922d329 100644
--- a/packages/babel-parser/src/plugins/typescript/index.js
+++ b/packages/babel-parser/src/plugins/typescript/index.js
@@ -14,8 +14,9 @@ import {
   BIND_TS_CONST_ENUM,
   BIND_TS_TYPE,
   BIND_TS_INTERFACE,
-  BIND_TS_FN_TYPE,
+  BIND_TS_AMBIENT,
   BIND_TS_NAMESPACE,
+  BIND_CLASS,
 } from "../../util/scopeflags";
 import TypeScriptScopeHandler from "./scope";
 
@@ -1278,6 +1279,9 @@ export default (superClass: Class<Parser>): Class<Parser> =>
             /* declarationPosition */ true,
           );
         case tt._class:
+          // While this is also set by tsParseExpressionStatement, we need to set it
+          // before parsing the class declaration to now how to register it in the scope.
+          nany.declare = true;
           return this.parseClass(
             nany,
             /* isStatement */ true,
@@ -1552,7 +1556,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
 
     checkFunctionStatementId(node: N.Function): void {
       if (!node.body && node.id) {
-        this.checkLVal(node.id, BIND_TS_FN_TYPE, null, "function name");
+        this.checkLVal(node.id, BIND_TS_AMBIENT, null, "function name");
       } else {
         super.checkFunctionStatementId(...arguments);
       }
@@ -1988,7 +1992,12 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         return;
       }
 
-      super.parseClassId(...arguments);
+      super.parseClassId(
+        node,
+        isStatement,
+        optionalId,
+        (node: any).declare ? BIND_TS_AMBIENT : BIND_CLASS,
+      );
       const typeParameters = this.tsTryParseTypeParameters();
       if (typeParameters) node.typeParameters = typeParameters;
     }
diff --git a/packages/babel-parser/src/plugins/typescript/scope.js b/packages/babel-parser/src/plugins/typescript/scope.js
index f706f1e88e..085b90e734 100644
--- a/packages/babel-parser/src/plugins/typescript/scope.js
+++ b/packages/babel-parser/src/plugins/typescript/scope.js
@@ -25,7 +25,7 @@ class TypeScriptScope extends Scope {
   // classes (which are also in .lexical) and interface (which are also in .types)
   classes: string[] = [];
 
-  // namespaces and bodyless-functions are too difficult to track,
+  // namespaces and ambient functions (or classes) are too difficult to track,
   // especially without type analysis.
   // We need to track them anyway, to avoid "X is not defined" errors
   // when exporting them.
diff --git a/packages/babel-parser/src/util/scopeflags.js b/packages/babel-parser/src/util/scopeflags.js
index 8c9697b3a4..43b18f6641 100644
--- a/packages/babel-parser/src/util/scopeflags.js
+++ b/packages/babel-parser/src/util/scopeflags.js
@@ -62,14 +62,14 @@ export const BIND_CLASS         = BIND_KIND_VALUE | BIND_KIND_TYPE | BIND_SCOPE_
              BIND_TS_INTERFACE  = 0               | BIND_KIND_TYPE | 0                   | BIND_FLAGS_CLASS  ,
              BIND_TS_TYPE       = 0               | BIND_KIND_TYPE | 0                   | 0                 ,
              BIND_TS_ENUM       = BIND_KIND_VALUE | BIND_KIND_TYPE | BIND_SCOPE_LEXICAL  | BIND_FLAGS_TS_ENUM,
-             BIND_TS_FN_TYPE    = 0               | 0              | 0            | BIND_FLAGS_TS_EXPORT_ONLY,
+             BIND_TS_AMBIENT    = 0               | 0              | 0            | BIND_FLAGS_TS_EXPORT_ONLY,
              // These bindings don't introduce anything in the scope. They are used for assignments and
              // function expressions IDs.
              BIND_NONE          = 0               | 0              | 0                   | BIND_FLAGS_NONE   ,
              BIND_OUTSIDE       = BIND_KIND_VALUE | 0              | 0                   | BIND_FLAGS_NONE   ,
 
              BIND_TS_CONST_ENUM = BIND_TS_ENUM | BIND_FLAGS_TS_CONST_ENUM,
-             BIND_TS_NAMESPACE  = BIND_TS_FN_TYPE;
+             BIND_TS_NAMESPACE  = 0               | 0              | 0            | BIND_FLAGS_TS_EXPORT_ONLY;
 
 export type BindingTypes =
   | typeof BIND_NONE
@@ -81,5 +81,5 @@ export type BindingTypes =
   | typeof BIND_TS_INTERFACE
   | typeof BIND_TS_TYPE
   | typeof BIND_TS_ENUM
-  | typeof BIND_TS_FN_TYPE
+  | typeof BIND_TS_AMBIENT
   | typeof BIND_TS_NAMESPACE;
diff --git a/packages/babel-parser/test/fixtures/typescript/scope/callable-class-ambient/input.ts b/packages/babel-parser/test/fixtures/typescript/scope/callable-class-ambient/input.ts
new file mode 100644
index 0000000000..7714551a24
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/typescript/scope/callable-class-ambient/input.ts
@@ -0,0 +1,2 @@
+declare class C { }
+declare function C(): void;
diff --git a/packages/babel-parser/test/fixtures/typescript/scope/callable-class-ambient/output.json b/packages/babel-parser/test/fixtures/typescript/scope/callable-class-ambient/output.json
new file mode 100644
index 0000000000..d62f3bba74
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/typescript/scope/callable-class-ambient/output.json
@@ -0,0 +1,151 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 47,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 2,
+      "column": 27
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 47,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 2,
+        "column": 27
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ClassDeclaration",
+        "start": 0,
+        "end": 19,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 19
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 14,
+          "end": 15,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 15
+            },
+            "identifierName": "C"
+          },
+          "name": "C"
+        },
+        "superClass": null,
+        "body": {
+          "type": "ClassBody",
+          "start": 16,
+          "end": 19,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 16
+            },
+            "end": {
+              "line": 1,
+              "column": 19
+            }
+          },
+          "body": []
+        },
+        "declare": true
+      },
+      {
+        "type": "TSDeclareFunction",
+        "start": 20,
+        "end": 47,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 27
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 37,
+          "end": 38,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 17
+            },
+            "end": {
+              "line": 2,
+              "column": 18
+            },
+            "identifierName": "C"
+          },
+          "name": "C"
+        },
+        "generator": false,
+        "async": false,
+        "params": [],
+        "returnType": {
+          "type": "TSTypeAnnotation",
+          "start": 40,
+          "end": 46,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 20
+            },
+            "end": {
+              "line": 2,
+              "column": 26
+            }
+          },
+          "typeAnnotation": {
+            "type": "TSVoidKeyword",
+            "start": 42,
+            "end": 46,
+            "loc": {
+              "start": {
+                "line": 2,
+                "column": 22
+              },
+              "end": {
+                "line": 2,
+                "column": 26
+              }
+            }
+          }
+        },
+        "declare": true
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/typescript/scope/callable-class/input.ts b/packages/babel-parser/test/fixtures/typescript/scope/callable-class/input.ts
new file mode 100644
index 0000000000..e54e510e93
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/typescript/scope/callable-class/input.ts
@@ -0,0 +1,2 @@
+declare class C { }
+function C() { }
diff --git a/packages/babel-parser/test/fixtures/typescript/scope/callable-class/output.json b/packages/babel-parser/test/fixtures/typescript/scope/callable-class/output.json
new file mode 100644
index 0000000000..205c683a02
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/typescript/scope/callable-class/output.json
@@ -0,0 +1,137 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 36,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 2,
+      "column": 16
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 36,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 2,
+        "column": 16
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ClassDeclaration",
+        "start": 0,
+        "end": 19,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 19
+          }
+        },
+        "declare": true,
+        "id": {
+          "type": "Identifier",
+          "start": 14,
+          "end": 15,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 15
+            },
+            "identifierName": "C"
+          },
+          "name": "C"
+        },
+        "superClass": null,
+        "body": {
+          "type": "ClassBody",
+          "start": 16,
+          "end": 19,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 16
+            },
+            "end": {
+              "line": 1,
+              "column": 19
+            }
+          },
+          "body": []
+        }
+      },
+      {
+        "type": "FunctionDeclaration",
+        "start": 20,
+        "end": 36,
+        "loc": {
+          "start": {
+            "line": 2,
+            "column": 0
+          },
+          "end": {
+            "line": 2,
+            "column": 16
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 29,
+          "end": 30,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 9
+            },
+            "end": {
+              "line": 2,
+              "column": 10
+            },
+            "identifierName": "C"
+          },
+          "name": "C"
+        },
+        "generator": false,
+        "async": false,
+        "params": [],
+        "body": {
+          "type": "BlockStatement",
+          "start": 33,
+          "end": 36,
+          "loc": {
+            "start": {
+              "line": 2,
+              "column": 13
+            },
+            "end": {
+              "line": 2,
+              "column": 16
+            }
+          },
+          "body": [],
+          "directives": []
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file
diff --git a/packages/babel-parser/test/fixtures/typescript/scope/redeclaration-import-ambient-class/input.ts b/packages/babel-parser/test/fixtures/typescript/scope/redeclaration-import-ambient-class/input.ts
new file mode 100644
index 0000000000..e57fcdb01a
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/typescript/scope/redeclaration-import-ambient-class/input.ts
@@ -0,0 +1,3 @@
+import Something from './somewhere.js'
+
+declare class Something {}
diff --git a/packages/babel-parser/test/fixtures/typescript/scope/redeclaration-import-ambient-class/output.json b/packages/babel-parser/test/fixtures/typescript/scope/redeclaration-import-ambient-class/output.json
new file mode 100644
index 0000000000..fe9e84eee5
--- /dev/null
+++ b/packages/babel-parser/test/fixtures/typescript/scope/redeclaration-import-ambient-class/output.json
@@ -0,0 +1,154 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 66,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 3,
+      "column": 26
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 66,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 3,
+        "column": 26
+      }
+    },
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ImportDeclaration",
+        "start": 0,
+        "end": 38,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 38
+          }
+        },
+        "specifiers": [
+          {
+            "type": "ImportDefaultSpecifier",
+            "start": 7,
+            "end": 16,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 7
+              },
+              "end": {
+                "line": 1,
+                "column": 16
+              }
+            },
+            "local": {
+              "type": "Identifier",
+              "start": 7,
+              "end": 16,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 7
+                },
+                "end": {
+                  "line": 1,
+                  "column": 16
+                },
+                "identifierName": "Something"
+              },
+              "name": "Something"
+            }
+          }
+        ],
+        "source": {
+          "type": "StringLiteral",
+          "start": 22,
+          "end": 38,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 22
+            },
+            "end": {
+              "line": 1,
+              "column": 38
+            }
+          },
+          "extra": {
+            "rawValue": "./somewhere.js",
+            "raw": "'./somewhere.js'"
+          },
+          "value": "./somewhere.js"
+        }
+      },
+      {
+        "type": "ClassDeclaration",
+        "start": 40,
+        "end": 66,
+        "loc": {
+          "start": {
+            "line": 3,
+            "column": 0
+          },
+          "end": {
+            "line": 3,
+            "column": 26
+          }
+        },
+        "declare": true,
+        "id": {
+          "type": "Identifier",
+          "start": 54,
+          "end": 63,
+          "loc": {
+            "start": {
+              "line": 3,
+              "column": 14
+            },
+            "end": {
+              "line": 3,
+              "column": 23
+            },
+            "identifierName": "Something"
+          },
+          "name": "Something"
+        },
+        "superClass": null,
+        "body": {
+          "type": "ClassBody",
+          "start": 64,
+          "end": 66,
+          "loc": {
+            "start": {
+              "line": 3,
+              "column": 24
+            },
+            "end": {
+              "line": 3,
+              "column": 26
+            }
+          },
+          "body": []
+        }
+      }
+    ],
+    "directives": []
+  }
+}
\ No newline at end of file