diff --git a/compiler/testData/diagnostics/wasmTests/jsInterop/external.kt b/compiler/testData/diagnostics/wasmTests/jsInterop/external.kt
new file mode 100644
index 00000000000..9ea151ca288
--- /dev/null
+++ b/compiler/testData/diagnostics/wasmTests/jsInterop/external.kt
@@ -0,0 +1,51 @@
+
+// Classes
+
+external class C1
+
+external enum class <!WRONG_EXTERNAL_DECLARATION!>C2<!>
+
+external annotation class <!WRONG_EXTERNAL_DECLARATION!>C3<!>
+
+external data class <!WRONG_EXTERNAL_DECLARATION!>C4(val x: String)<!>
+
+external class C5 {
+
+    class C6
+
+    inner class <!WRONG_EXTERNAL_DECLARATION!>C7<!>
+}
+
+external <!INLINE_CLASS_DEPRECATED!>inline<!> class <!WRONG_EXTERNAL_DECLARATION!>C8(<!EXTERNAL_CLASS_CONSTRUCTOR_PROPERTY_PARAMETER!>val x: Int<!>)<!>
+
+external value class <!WRONG_EXTERNAL_DECLARATION!>C9(<!EXTERNAL_CLASS_CONSTRUCTOR_PROPERTY_PARAMETER!>val x: Int<!>)<!>
+
+
+// Interfaces
+
+external interface I1
+
+external fun interface <!WRONG_EXTERNAL_DECLARATION!>I2<!> {
+    fun foo(): Int
+}
+
+
+// Functions
+
+external fun foo1(): Int
+
+<!WRONG_EXTERNAL_DECLARATION!>external tailrec fun foo2(): Int<!>
+
+<!INLINE_EXTERNAL_DECLARATION!>external inline fun foo3(f: () -> Int): Int<!>
+
+<!WRONG_EXTERNAL_DECLARATION!>external suspend fun foo4(): Int<!>
+
+<!WRONG_EXTERNAL_DECLARATION!>external fun Int.foo5(): Int<!>
+
+
+// Properties
+
+<!WRONG_EXTERNAL_DECLARATION!>external lateinit var v1: String<!>
+
+<!WRONG_EXTERNAL_DECLARATION!>external val Int.v2: String<!>
+    get() = definedExternally
\ No newline at end of file
diff --git a/wasm/wasm.frontend/src/org/jetbrains/kotlin/wasm/resolve/WasmPlatformConfigurator.kt b/wasm/wasm.frontend/src/org/jetbrains/kotlin/wasm/resolve/WasmPlatformConfigurator.kt
index d210379822f..e8890c58568 100644
--- a/wasm/wasm.frontend/src/org/jetbrains/kotlin/wasm/resolve/WasmPlatformConfigurator.kt
+++ b/wasm/wasm.frontend/src/org/jetbrains/kotlin/wasm/resolve/WasmPlatformConfigurator.kt
@@ -15,6 +15,7 @@ import org.jetbrains.kotlin.js.resolve.diagnostics.*
 import org.jetbrains.kotlin.resolve.PlatformConfiguratorBase
 import org.jetbrains.kotlin.resolve.calls.checkers.LateinitIntrinsicApplicabilityChecker
 import org.jetbrains.kotlin.resolve.checkers.ExpectedActualDeclarationChecker
+import org.jetbrains.kotlin.wasm.resolve.diagnostics.WasmExternalDeclarationChecker
 import org.jetbrains.kotlin.wasm.resolve.diagnostics.WasmExternalInheritanceChecker
 
 // TODO: Review the list of used K/JS checkers.
@@ -26,6 +27,7 @@ object WasmPlatformConfigurator : PlatformConfiguratorBase(
         JsRuntimeAnnotationChecker,
         JsExportAnnotationChecker,
         JsExportDeclarationChecker,
+        WasmExternalDeclarationChecker,
     ),
     additionalCallCheckers = listOf(
         JsModuleCallChecker,
diff --git a/wasm/wasm.frontend/src/org/jetbrains/kotlin/wasm/resolve/diagnostics/WasmExternalDeclarationChecker.kt b/wasm/wasm.frontend/src/org/jetbrains/kotlin/wasm/resolve/diagnostics/WasmExternalDeclarationChecker.kt
new file mode 100644
index 00000000000..e815b57f54d
--- /dev/null
+++ b/wasm/wasm.frontend/src/org/jetbrains/kotlin/wasm/resolve/diagnostics/WasmExternalDeclarationChecker.kt
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2010-2016 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.kotlin.wasm.resolve.diagnostics
+
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.descriptors.MemberDescriptor
+import org.jetbrains.kotlin.descriptors.PropertyDescriptor
+import org.jetbrains.kotlin.descriptors.isEnumClass
+import org.jetbrains.kotlin.js.resolve.diagnostics.ErrorsJs
+import org.jetbrains.kotlin.psi.KtDeclaration
+import org.jetbrains.kotlin.resolve.checkers.DeclarationChecker
+import org.jetbrains.kotlin.resolve.checkers.DeclarationCheckerContext
+import org.jetbrains.kotlin.resolve.descriptorUtil.isEffectivelyExternal
+
+// TODO: Implement in K2: KT-56849
+object WasmExternalDeclarationChecker : DeclarationChecker {
+    override fun check(declaration: KtDeclaration, descriptor: DeclarationDescriptor, context: DeclarationCheckerContext) {
+        if (descriptor !is MemberDescriptor || !descriptor.isEffectivelyExternal())
+            return
+
+        fun reportWrongExternalDeclaration(kind: String) {
+            context.trace.report(ErrorsJs.WRONG_EXTERNAL_DECLARATION.on(declaration, kind))
+        }
+
+        when (descriptor) {
+            is ClassDescriptor -> {
+                if (descriptor.kind.isEnumClass) {
+                    reportWrongExternalDeclaration("enum class")
+                }
+            }
+            is PropertyDescriptor -> {
+                if (descriptor.isLateInit) {
+                    reportWrongExternalDeclaration("lateinit property")
+                }
+            }
+            is FunctionDescriptor -> {
+                if (descriptor.isTailrec) {
+                    reportWrongExternalDeclaration("tailrec function")
+                }
+                if (descriptor.isSuspend) {
+                    reportWrongExternalDeclaration("suspend function")
+                }
+            }
+        }
+    }
+}
diff --git a/wasm/wasm.tests/tests-gen/org/jetbrains/kotlin/wasm/test/diagnostics/DiagnosticsWasmTestGenerated.java b/wasm/wasm.tests/tests-gen/org/jetbrains/kotlin/wasm/test/diagnostics/DiagnosticsWasmTestGenerated.java
index 60f43c7e339..217244e3c8d 100644
--- a/wasm/wasm.tests/tests-gen/org/jetbrains/kotlin/wasm/test/diagnostics/DiagnosticsWasmTestGenerated.java
+++ b/wasm/wasm.tests/tests-gen/org/jetbrains/kotlin/wasm/test/diagnostics/DiagnosticsWasmTestGenerated.java
@@ -39,6 +39,12 @@ public class DiagnosticsWasmTestGenerated extends AbstractDiagnosticsWasmTest {
             runTest("compiler/testData/diagnostics/wasmTests/jsInterop/dynamicUnsupported.kt");
         }
 
+        @Test
+        @TestMetadata("external.kt")
+        public void testExternal() throws Exception {
+            runTest("compiler/testData/diagnostics/wasmTests/jsInterop/external.kt");
+        }
+
         @Test
         @TestMetadata("inheritance.kt")
         public void testInheritance() throws Exception {