diff --git a/src/embed_tests/TestInterrupt.cs b/src/embed_tests/TestInterrupt.cs
index a40407782..e344a8ccb 100644
--- a/src/embed_tests/TestInterrupt.cs
+++ b/src/embed_tests/TestInterrupt.cs
@@ -11,22 +11,51 @@ namespace Python.EmbeddingTest
 {
     public class TestInterrupt
     {
-        private IntPtr _threadState;
-
+        PyObject threading;
         [OneTimeSetUp]
         public void SetUp()
         {
             PythonEngine.Initialize();
-            _threadState = PythonEngine.BeginAllowThreads();
+            // workaround for assert tlock.locked() warning
+            threading = Py.Import("threading");
         }
 
         [OneTimeTearDown]
         public void Dispose()
         {
-            PythonEngine.EndAllowThreads(_threadState);
+            threading.Dispose();
             PythonEngine.Shutdown();
         }
 
+        [Test]
+        public void PythonThreadIDStable()
+        {
+            long pythonThreadID = 0;
+            long pythonThreadID2 = 0;
+            var asyncCall = Task.Factory.StartNew(() =>
+            {
+                using (Py.GIL())
+                {
+                    Interlocked.Exchange(ref pythonThreadID, (long)PythonEngine.GetPythonThreadID());
+                    Interlocked.Exchange(ref pythonThreadID2, (long)PythonEngine.GetPythonThreadID());
+                }
+            });
+
+            var timeout = Stopwatch.StartNew();
+
+            IntPtr threadState = PythonEngine.BeginAllowThreads();
+            while (Interlocked.Read(ref pythonThreadID) == 0 || Interlocked.Read(ref pythonThreadID2) == 0)
+            {
+                Assert.Less(timeout.Elapsed, TimeSpan.FromSeconds(5), "thread IDs were not assigned in time");
+            }
+            PythonEngine.EndAllowThreads(threadState);
+
+            Assert.IsTrue(asyncCall.Wait(TimeSpan.FromSeconds(5)), "Async thread has not finished in time");
+
+            Assert.AreEqual(pythonThreadID, pythonThreadID2);
+            Assert.NotZero(pythonThreadID);
+        }
+
         [Test]
         public void InterruptTest()
         {
@@ -39,26 +68,31 @@ public void InterruptTest()
                     return PythonEngine.RunSimpleString(@"
 import time
 
-while True:
-    time.sleep(0.2)");
+try:
+  while True:
+    time.sleep(0.2)
+except KeyboardInterrupt:
+  pass");
                 }
             });
 
             var timeout = Stopwatch.StartNew();
+
+            IntPtr threadState = PythonEngine.BeginAllowThreads();
             while (Interlocked.Read(ref pythonThreadID) == 0)
             {
                 Assert.Less(timeout.Elapsed, TimeSpan.FromSeconds(5), "thread ID was not assigned in time");
             }
+            PythonEngine.EndAllowThreads(threadState);
 
-            using (Py.GIL())
-            {
-                int interruptReturnValue = PythonEngine.Interrupt((ulong)Interlocked.Read(ref pythonThreadID));
-                Assert.AreEqual(1, interruptReturnValue);
-            }
+            int interruptReturnValue = PythonEngine.Interrupt((ulong)Interlocked.Read(ref pythonThreadID));
+            Assert.AreEqual(1, interruptReturnValue);
 
+            threadState = PythonEngine.BeginAllowThreads();
             Assert.IsTrue(asyncCall.Wait(TimeSpan.FromSeconds(5)), "Async thread was not interrupted in time");
+            PythonEngine.EndAllowThreads(threadState);
 
-            Assert.AreEqual(-1, asyncCall.Result);
+            Assert.AreEqual(0, asyncCall.Result);
         }
     }
 }
diff --git a/src/runtime/pythonengine.cs b/src/runtime/pythonengine.cs
index 4b72dabd7..cd608fe93 100644
--- a/src/runtime/pythonengine.cs
+++ b/src/runtime/pythonengine.cs
@@ -570,8 +570,9 @@ internal static void Exec(string code, BorrowedReference globals, BorrowedRefere
         /// <returns>The Python thread ID.</returns>
         public static ulong GetPythonThreadID()
         {
-            dynamic threading = Py.Import("threading");
-            return threading.InvokeMethod("get_ident");
+            using PyObject threading = Py.Import("threading");
+            using PyObject id = threading.InvokeMethod("get_ident");
+            return id.As<ulong>();
         }
 
         /// <summary>