UNITED NATIONS, May 7: Saying that lives of some witnesses could be at stake, the head of the UN’s oil-for-food inquiry committee on Friday accused the US Congress of jeopardizing his work and asked a House committee to return secret documents it had obtained through a former investigator.

At a news conference following revelations that a former FBI agent, Robert Parton, had handed over documents to the US Congress, former Federal Reserve chairman Paul Volcker said there simply was never enough evidence to prove that UN chief Kofi Annan had influenced the awarding of a contract to the Swiss company that employed his son.

But Mr Volcker insisted that his committee’s report was not the exoneration that Kofi Annan claimed it was.

“We’re not playing games here, we are dealing — and let me just emphasize this — in some cases with lives,” Mr Volcker said.

He also asked the House International Relations Committee to return secret documents Mr Parton gave it, warning that witnesses’ lives could be endangered if anything leaked out.

But Illinois Republican Henry Hyde, chairman of the committee, rejected the request, saying that he appreciated ‘the gravity of the concerns’’ but his panel had ‘an obligation to continue its inquiry’.