diff --git a/core/src/main/java/org/teavm/backend/javascript/rendering/Renderer.java b/core/src/main/java/org/teavm/backend/javascript/rendering/Renderer.java
index 8e082c21b..17712be79 100644
--- a/core/src/main/java/org/teavm/backend/javascript/rendering/Renderer.java
+++ b/core/src/main/java/org/teavm/backend/javascript/rendering/Renderer.java
@@ -363,16 +363,7 @@ public class Renderer implements RenderingManager {
             }
 
             if (needsClinit) {
-                writer.append("function ").appendClass(cls.getName()).append("_$callClinit()").ws()
-                        .append("{").softNewLine().indent();
-                writer.appendClass(cls.getName()).append("_$callClinit").ws().append("=").ws()
-                        .append("function(){};").newLine();
-                for (MethodNode method : clinitMethods) {
-                    renderBody(method, true);
-                }
-                writer.appendMethodBody(new MethodReference(cls.getName(), clinit.getDescriptor()))
-                        .append("();").softNewLine();
-                writer.outdent().append("}").newLine();
+                renderCallClinit(clinit, cls, clinitMethods);
             }
             if (!cls.getModifiers().contains(ElementModifier.INTERFACE)) {
                 for (MethodNode method : cls.getMethods()) {
@@ -396,6 +387,71 @@ public class Renderer implements RenderingManager {
         debugEmitter.emitClass(null);
     }
 
+    private void renderCallClinit(MethodReader clinit, ClassNode cls, List<MethodNode> clinitMethods)
+            throws IOException {
+        boolean isAsync = asyncMethods.contains(clinit.getReference());
+
+        if (isAsync) {
+            writer.append("var ").appendClass(cls.getName()).append("_$clinitCalled").ws().append("=").ws()
+                    .append("false;").softNewLine();
+        }
+
+        writer.append("function ").appendClass(cls.getName()).append("_$callClinit()").ws()
+                .append("{").softNewLine().indent();
+
+        if (isAsync) {
+            writer.append("var ").append(context.pointerName()).ws().append("=").ws()
+                    .append("0").append(";").softNewLine();
+            writer.append("if").ws().append("(").appendFunction("$rt_resuming").append("())").ws().append("{")
+                    .indent().softNewLine();
+            writer.append(context.pointerName()).ws().append("=").ws().appendFunction("$rt_nativeThread")
+                    .append("().pop();").softNewLine();
+            writer.outdent().append("}").ws();
+            writer.append("else if").ws().append("(").appendClass(cls.getName()).append("_$clinitCalled)").ws()
+                    .append("{").indent().softNewLine();
+            writer.append("return;").softNewLine();
+            writer.outdent().append("}").softNewLine();
+
+            renderAsyncPrologue();
+
+            writer.append("case 0:").indent().softNewLine();
+            writer.appendClass(cls.getName()).append("_$clinitCalled").ws().append('=').ws().append("true;")
+                    .softNewLine();
+        } else {
+            renderEraseClinit(cls);
+            for (MethodNode method : clinitMethods) {
+                renderBody(method, true);
+            }
+        }
+
+        if (isAsync) {
+            writer.append(context.pointerName()).ws().append("=").ws().append("1;").softNewLine();
+            writer.outdent().append("case 1:").indent().softNewLine();
+        }
+
+        writer.appendMethodBody(new MethodReference(cls.getName(), clinit.getDescriptor()))
+                .append("();").softNewLine();
+
+        if (isAsync) {
+            writer.append("if").ws().append("(").appendFunction("$rt_suspending").append("())").ws().append("{")
+                    .indent().softNewLine();
+            writer.append("break " + context.mainLoopName() + ";").softNewLine();
+            writer.outdent().append("}").softNewLine();
+            renderEraseClinit(cls);
+            writer.append("return;").softNewLine().outdent();
+
+            renderAsyncEpilogue();
+            writer.appendFunction("$rt_nativeThread").append("().push(" + context.pointerName() + ");").softNewLine();
+        }
+
+        writer.outdent().append("}").newLine();
+    }
+
+    private void renderEraseClinit(ClassNode cls) throws IOException {
+        writer.appendClass(cls.getName()).append("_$callClinit").ws().append("=").ws()
+                .append("function(){};").newLine();
+    }
+
     private void renderClassMetadata(List<ClassNode> classes) {
         try {
             writer.append("$rt_metadata([");
@@ -598,6 +654,18 @@ public class Renderer implements RenderingManager {
         debugEmitter.emitMethod(null);
     }
 
+    private void renderAsyncPrologue() throws IOException {
+        writer.append(context.mainLoopName()).append(":").ws().append("while").ws().append("(true)")
+                .ws().append("{").ws();
+        writer.append("switch").ws().append("(").append(context.pointerName()).append(")").ws()
+                .append('{').softNewLine();
+    }
+
+    private void renderAsyncEpilogue() throws IOException {
+        writer.append("default:").ws().appendFunction("$rt_invalidPointer").append("();").softNewLine();
+        writer.append("}}").softNewLine();
+    }
+
     private class MethodBodyRenderer implements MethodNodeVisitor, GeneratorContext {
         private boolean async;
         private StatementRenderer statementRenderer;
@@ -726,10 +794,8 @@ public class Renderer implements RenderingManager {
                 if (methodNode.getModifiers().contains(ElementModifier.SYNCHRONIZED)) {
                     writer.append("try").ws().append('{').indent().softNewLine();
                 }
-                writer.append(context.mainLoopName()).append(":").ws().append("while").ws().append("(true)")
-                        .ws().append("{").ws();
-                writer.append("switch").ws().append("(").append(context.pointerName()).append(")").ws()
-                        .append('{').softNewLine();
+
+                renderAsyncPrologue();
                 for (int i = 0; i < methodNode.getBody().size(); ++i) {
                     writer.append("case ").append(i).append(":").indent().softNewLine();
                     if (i == 0 && methodNode.getModifiers().contains(ElementModifier.SYNCHRONIZED)) {
@@ -746,8 +812,7 @@ public class Renderer implements RenderingManager {
                     part.getStatement().acceptVisitor(statementRenderer);
                     writer.outdent();
                 }
-                writer.append("default:").ws().appendFunction("$rt_invalidPointer").append("();").softNewLine();
-                writer.append("}}").softNewLine();
+                renderAsyncEpilogue();
 
                 if (methodNode.getModifiers().contains(ElementModifier.SYNCHRONIZED)) {
                     writer.outdent().append("}").ws().append("finally").ws().append('{').indent().softNewLine();
diff --git a/core/src/main/resources/org/teavm/backend/javascript/runtime.js b/core/src/main/resources/org/teavm/backend/javascript/runtime.js
index 4288b39eb..e9e4eb65e 100644
--- a/core/src/main/resources/org/teavm/backend/javascript/runtime.js
+++ b/core/src/main/resources/org/teavm/backend/javascript/runtime.js
@@ -406,10 +406,25 @@ function $rt_metadata(data) {
         for (var j = 0; j < names.length; j = (j + 1) | 0) {
             window[names[j]] = (function(cls, name) {
                 return function() {
-                    var clinit = cls.$clinit;
-                    cls.$clinit = function() {};
-                    clinit();
-                    return window[name].apply(window, arguments);
+                    var ptr = 0;
+                    if ($rt_resuming()) {
+                        ptr = $rt_nativeThread().pop();
+                    }
+                    main: while (true) {
+                        switch (ptr) {
+                            case 0:
+                                clinit = cls.$clinit;
+                                clinit();
+                                ptr = 1;
+                            case 1:
+                                var result = window[name].apply(window, arguments);
+                                if ($rt_suspend()) {
+                                    break;
+                                }
+                                return result;
+                        }
+                    }
+                    $rt_nativeThread().push(ptr);
                 }
             })(cls, names[j]);
         }
diff --git a/platform/src/main/java/org/teavm/platform/plugin/AsyncMethodProcessor.java b/platform/src/main/java/org/teavm/platform/plugin/AsyncMethodProcessor.java
index b3d77e44c..c79de90d0 100644
--- a/platform/src/main/java/org/teavm/platform/plugin/AsyncMethodProcessor.java
+++ b/platform/src/main/java/org/teavm/platform/plugin/AsyncMethodProcessor.java
@@ -19,7 +19,6 @@ import org.teavm.backend.javascript.spi.GeneratedBy;
 import org.teavm.dependency.PluggableDependency;
 import org.teavm.diagnostics.Diagnostics;
 import org.teavm.interop.Async;
-import org.teavm.interop.Sync;
 import org.teavm.model.AnnotationHolder;
 import org.teavm.model.AnnotationValue;
 import org.teavm.model.CallLocation;
@@ -32,10 +31,6 @@ import org.teavm.model.MethodHolder;
 import org.teavm.model.ValueType;
 import org.teavm.platform.async.AsyncCallback;
 
-/**
- *
- * @author Alexey Andreev
- */
 public class AsyncMethodProcessor implements ClassHolderTransformer {
     @Override
     public void transformClass(ClassHolder cls, ClassReaderSource innerSource, Diagnostics diagnostics) {
@@ -65,11 +60,6 @@ public class AsyncMethodProcessor implements ClassHolderTransformer {
                     annot.getValues().put("value", new AnnotationValue(ValueType.parse(AsyncMethodGenerator.class)));
                     method.getAnnotations().add(annot);
                 }
-            } else if (method.getName().equals("<clinit>")) {
-                if (method.getAnnotations().get(Sync.class.getName()) == null) {
-                    AnnotationHolder annot = new AnnotationHolder(Sync.class.getName());
-                    method.getAnnotations().add(annot);
-                }
             }
         }
     }
diff --git a/tests/src/test/java/org/teavm/vm/VMTest.java b/tests/src/test/java/org/teavm/vm/VMTest.java
index b5dfc8169..be749aca3 100644
--- a/tests/src/test/java/org/teavm/vm/VMTest.java
+++ b/tests/src/test/java/org/teavm/vm/VMTest.java
@@ -116,6 +116,41 @@ public class VMTest {
         assertEquals(x, id(23));
     }
 
+    @Test
+    public void asyncClinit() {
+        assertEquals(0, initCount);
+        assertEquals("foo", AsyncClinitClass.foo());
+        assertEquals(1, initCount);
+        assertEquals(AsyncClinitClass.state, "ok");
+        assertEquals("bar", AsyncClinitClass.bar());
+        assertEquals(1, initCount);
+        assertEquals(AsyncClinitClass.state, "ok");
+    }
+
+    static int initCount = 0;
+
+    private static class AsyncClinitClass {
+        static String state = "";
+
+        static {
+            initCount++;
+            try {
+                Thread.sleep(1);
+                state += "ok";
+            } catch (InterruptedException e) {
+                state += "error";
+            }
+        }
+
+        public static String foo() {
+            return "foo";
+        }
+
+        public static String bar() {
+            return "bar";
+        }
+    }
+
     private void throwException() {
         throw new RuntimeException();
     }