diff --git a/packages/TypeDeclaration/src/Rector/FunctionLike/ReturnTypeDeclarationRector.php b/packages/TypeDeclaration/src/Rector/FunctionLike/ReturnTypeDeclarationRector.php
index 686187cfc7ae..cb4d3b763dfc 100644
--- a/packages/TypeDeclaration/src/Rector/FunctionLike/ReturnTypeDeclarationRector.php
+++ b/packages/TypeDeclaration/src/Rector/FunctionLike/ReturnTypeDeclarationRector.php
@@ -145,6 +145,13 @@ public function refactor(Node $node): ?Node
                 }
             }
 
+            // nullable aase
+            if ($currentType instanceof UnionType && $inferedType instanceof UnionType) {
+                if ($inferedType->isSubTypeOf($currentType)->yes()) {
+                    return null;
+                }
+            }
+
             // @see https://wiki.php.net/rfc/covariant-returns-and-contravariant-parameters
             if ($this->isAtLeastPhpVersion('7.4') && $isSubtype) {
                 $node->returnType = $inferredReturnNode;
diff --git a/packages/TypeDeclaration/tests/Rector/FunctionLike/ReturnTypeDeclarationRector/Fixture/issue2383.php.inc b/packages/TypeDeclaration/tests/Rector/FunctionLike/ReturnTypeDeclarationRector/Fixture/issue2383.php.inc
new file mode 100644
index 000000000000..eb43e52f6d01
--- /dev/null
+++ b/packages/TypeDeclaration/tests/Rector/FunctionLike/ReturnTypeDeclarationRector/Fixture/issue2383.php.inc
@@ -0,0 +1,25 @@
+<?php
+
+namespace Rector\TypeDeclaration\Tests\Rector\FunctionLike\ReturnTypeDeclarationRector\Fixture\IterableFunction;
+
+class Issus2383
+{
+    public function go(): ?UriInterface
+    {
+        if (rand()) {
+            return new UriImplementation();
+        }
+
+        return null;
+    }
+}
+
+interface UriInterface
+{
+
+}
+
+class UriImplementation implements UriInterface
+{
+
+}
\ No newline at end of file