It said Mr Galloway’s name had been pasted on to a list of people and companies alleged to have made money out of the Oil For Food programme.

His name appeared in a different typeface to other words on the same line, the print was lighter in colour and Respect suggested it had been stuck on and then the page re-photocopied.

His name also appeared at a slight angle and Respect said that would be impossible on the computerised document unless it had been artificially added.

Mr Galloway’s party said there was a clear link between the list in the Senate Committee’s report and one which appeared in a Baghdad newspaper in January last year.

Respect highlighted the claims of Sajad Ahmad Ali, who has previously claimed to have been involved in forging that list.

Mr Ali said: “We forged this list of names and titles of people who got money from the Ministry of Information, the palace and the Oil For Food.

“We worked for 10 days and then we steamed the papers a bit then dried them out so that they would look old.

“I beg anyone who reads his name in these papers to ask for the original version and check the date of the writing with carbon dating.”

A spokesman for Respect said: “We know forgeries were being produced and one is being used in evidence.

“We don’t have to prove an international conspiracy nor are we alleging one but we are saying that there is a forgery here.

“This is the only documentary evidence. The question to the committee should be what steps did they take to verify this document?

“The actual first document, we don’t know where it is, they don’t know where it is and all they have is a photocopy handed over by an unnamed source.”

The UN-backed Oil For Food scheme enabled Saddam Hussein to export oil to pay for essential humanitarian goo help the Iraqi people cope with sanctions imposed in 1991. Theell its oil for cash.

Saddam sold the vouchers at below market prices to favoured parties who were able to sell them on at a profit.

The US Senate Committee accused Mr Galloway of receiving vouchers for millions of barrels of oil but he has described the allegations as “absurd” and asked to appear before them promising to “give them both barrels” in what is expected to be a dramatic highly-charged exchange.