Iraq's ex-deputy prime minister Tariq Aziz has denied accusing George Galloway of profiting from the oil for food programme, the anti-war MP says.
Mr Galloway has denied dealing oil on several occasions
A US Senate committee report based on interviews with Aziz said the MP received oil from the Iraqi regime.
After meeting Mr Aziz's lawyers in Paris, Mr Galloway said the former senior Iraqi politician had denied ever saying he benefited from the scheme.
Mr Galloway said the case against him was based on a "grand lie".
After a long meeting with two French lawyers, Mr Galloway said: "Tariq Aziz absolutely denies ever saying that I benefited from oil deals or that I talked to him about oil allocations."
Mr Galloway accused Republican Senator Norm Coleman, who has led the accusations against the former Labour MP, of using "shadowy sources" and making up the evidence.
He also demanded that Senator Coleman publicly clear his name.
A spokesman for the senator dismissed Mr Galloway's claims, pointing to a series of documents which he said clearly supported the allegations.
"The principal evidence of wire transfer records and banking statements prove that oil-for-food money went into Galloway's political campaign and his wife's bank account."
The senate committee's report this week said Mr Aziz had told investigators that Mr Galloway requested oil allocations in the name of Fawaz Zureikat, a Jordanian businessman and friend of the MP.
And a UN-backed investigation, written by ex-US Federal Reserve chairman Paul Volcker, alleged more than 11 million barrels of oil were allocated in the Respect MP's name.
But the UN report says Mr Aziz changed that version of events in a second interview but that it did not find this credible.
About 2,000 companies were also accused of giving kickbacks to Saddam Hussein's regime in the report.
The report cited "Iraqi oil officials" as the source of claims that allocations were granted to Mr Galloway to fund his campaign against sanctions imposed on Iraq after the 1990 invasion of Kuwait.
The author of the report acknowledged Mr Galloway's denial of involvement in the scheme and his insistence that he had not received any proceeds from oil sales.
The oil-for-food scheme was set up in an attempt to ease the hardship faced by Iraqi people following the imposition of economic sanctions.
Under the programme, Saddam Hussein's government was allowed to sell oil as long as the proceeds were used to buy humanitarian goods.
The report found that companies buying the oil at cut prices would funnel extra money to Iraq through surcharges, while those receiving money from Iraq for humanitarian goods and services would return a portion in kickbacks.
Mr Volcker said the corruption would not have been so pervasive had there been better discipline by UN management.