Senator Brutti also told reporters that Italian intelligence had warned Washington in early 2003 that the Niger-Iraq documents were false.

"At about the same time as the State of the Union address, they said that the dossier doesn't correspond to the truth," Senator Brutti said. He said he did not know whether the warning was given before or after President Bush's address.

He made the claim more than once, but gave no supporting evidence. Amid confusing statements by various lawmakers, he later appeared to backtrack in conversations with both The Associated Press and Reuters, saying that because Sismi never had the documents, it could not comment on their merit.

There had long been doubts within the United States intelligence community about the authenticity of the yellowcake documents, and references to it had been deleted from other presentations given at the time.