diff --git a/haystack_experimental/components/extractors/llm_metadata_extractor.py b/haystack_experimental/components/extractors/llm_metadata_extractor.py
index 8528e26e..89af8396 100644
--- a/haystack_experimental/components/extractors/llm_metadata_extractor.py
+++ b/haystack_experimental/components/extractors/llm_metadata_extractor.py
@@ -151,7 +151,7 @@ def __init__( # pylint: disable=R0917
     def _init_generator(
             generator_api: LLMProvider,
             generator_api_params: Optional[Dict[str, Any]]
-    ) -> Union[OpenAIGenerator, AzureOpenAIGenerator, AmazonBedrockGenerator, VertexAIGeminiGenerator]:
+    ) -> Union[OpenAIGenerator, AzureOpenAIGenerator, "AmazonBedrockGenerator", "VertexAIGeminiGenerator"]:
         """
         Initialize the chat generator based on the specified API provider and parameters.
         """