diff --git a/compiler/testData/cli/js/legacyCompilerUsageWithoutFlag.args b/compiler/testData/cli/js/legacyCompilerUsageWithoutFlag.args
new file mode 100644
index 00000000000..d99fe90b79c
--- /dev/null
+++ b/compiler/testData/cli/js/legacyCompilerUsageWithoutFlag.args
@@ -0,0 +1,3 @@
+$TESTDATA_DIR$/simple2js.kt
+-output
+$TEMP_DIR$/out.js
diff --git a/compiler/testData/cli/js/legacyCompilerUsageWithoutFlag.out b/compiler/testData/cli/js/legacyCompilerUsageWithoutFlag.out
new file mode 100644
index 00000000000..a33af2c6697
--- /dev/null
+++ b/compiler/testData/cli/js/legacyCompilerUsageWithoutFlag.out
@@ -0,0 +1,2 @@
+error: old Kotlin/JS compiler is no longer supported. Please migrate to the new JS IR backend
+COMPILATION_ERROR
diff --git a/compiler/tests-gen/org/jetbrains/kotlin/cli/CliTestGenerated.java b/compiler/tests-gen/org/jetbrains/kotlin/cli/CliTestGenerated.java
index 1fae0c082df..ede645c6deb 100644
--- a/compiler/tests-gen/org/jetbrains/kotlin/cli/CliTestGenerated.java
+++ b/compiler/tests-gen/org/jetbrains/kotlin/cli/CliTestGenerated.java
@@ -1363,6 +1363,11 @@ public class CliTestGenerated extends AbstractCliTest {
             runTest("compiler/testData/cli/js/languageVersion.args");
         }
 
+        @TestMetadata("legacyCompilerUsageWithoutFlag.args")
+        public void testLegacyCompilerUsageWithoutFlag() throws Exception {
+            runTest("compiler/testData/cli/js/legacyCompilerUsageWithoutFlag.args");
+        }
+
         @TestMetadata("libraryDirNotFound.args")
         public void testLibraryDirNotFound() throws Exception {
             runTest("compiler/testData/cli/js/libraryDirNotFound.args");
diff --git a/libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/tasks/Kotlin2JsCompile.kt b/libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/tasks/Kotlin2JsCompile.kt
index 5f2bfe713b6..f98ef4308d7 100644
--- a/libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/tasks/Kotlin2JsCompile.kt
+++ b/libraries/tools/kotlin-gradle-plugin/src/common/kotlin/org/jetbrains/kotlin/gradle/tasks/Kotlin2JsCompile.kt
@@ -158,10 +158,6 @@ abstract class Kotlin2JsCompile @Inject constructor(
                 args.fragmentRefines = multiplatformStructure.fragmentRefinesCompilerArgs
             }
 
-            if (!isIrBackendEnabled()) {
-                args.forceDeprecatedLegacyCompilerUsage = true
-            }
-
             // Overriding freeArgs from compilerOptions with enhanced one + additional one set on execution phase
             // containing additional arguments based on the js compilation configuration
             args.freeArgs = executionTimeFreeCompilerArgs ?: enhancedFreeCompilerArgs.get()
diff --git a/plugins/atomicfu/atomicfu-runtime/build.gradle.kts b/plugins/atomicfu/atomicfu-runtime/build.gradle.kts
index 58c6cf4185b..6b52d718e15 100644
--- a/plugins/atomicfu/atomicfu-runtime/build.gradle.kts
+++ b/plugins/atomicfu/atomicfu-runtime/build.gradle.kts
@@ -37,3 +37,7 @@ publishing {
         }
     }
 }
+
+tasks.withType<org.jetbrains.kotlin.gradle.dsl.KotlinJsCompile> {
+    kotlinOptions.freeCompilerArgs += "-Xforce-deprecated-legacy-compiler-usage"
+}
\ No newline at end of file