UK MP George Galloway could face a new inquiry into the finances of an appeal he set up to help a sick Iraqi girl.
George Galloway denies claims he profited from Iraqi oil deals
The Charity Commission has said it will contact US senators investigating claims Mr Galloway was given credits for Iraqi oil by Saddam Hussein.
The UK body is keen to see US evidence concerning Mr Galloway's Mariam Appeal.
The MP denies funds from the sale of oil were funnelled through the appeal. He told senators a previous Commission inquiry had found no impropriety.
Mr Galloway received a jubilant welcome on Wednesday evening as hundreds of people turned up for a Respect meeting to celebrate his election victory in Bethnal and Bow, east London.
One of the party's candidates, Abdul Khaliq Mian, said: "He blasted the whole of the US Senate."
On Tuesday, Mr Galloway accused the US Senate investigations sub-committee of being "cavalier" with justice during his appearance in Washington.
He said the Commission's inquiry into the appeal, set up in 1998 to help a four-year-old Iraqi girl with leukaemia, had recovered "all money in and all money out".
However, the head of legal services for the Charity Commission, Kenneth Dibble, said there had been "limitations" on its investigation.
Some of the records for the appeal had been taken out of the country by its then chairman, Jordanian businessman Fawaz Zureikat, Mr Dibble told BBC Radio 4's Today programme.
This meant investigators had to "reconstruct" the income and expenditure of the appeal fund by looking at its bank accounts, he said.
"With the help of the trustees... we were able to establish at least that the majority of the monies were applied for purposes that were charitable," he said.
The Charity Commission has now asked to see the US senators' evidence in order to establish if further action is needed.
Mr Dibble said: "We would have to consider whether or not they were aware of any improper nature of funds coming to the charity if indeed we find there is evidence to support that."
'No oil deal'
No-one was available to comment at Mr Galloway's office.
Speaking after the Senate hearing, Mr Galloway claimed victory in his fight to clear his name.
The Respect MP claims the evidence against him is false. He says forged documents have been used against him in the past.
One of the main allegations raised by the Senate sub-committee is that Mr Galloway received oil allocations with the assistance of Mr Zureikat.
The Mariam Appeal was set up to help an Iraqi girl with leukaemia
The UN-backed oil-for-food scheme enabled Saddam Hussein to export oil to pay for essential humanitarian aid to help the Iraqi people cope with UN sanctions imposed in 1991.
Options to buy barrels of Iraqi oil were alleged to have been given as rewards for supporting Saddam.
The MP said Mr Zureikat had donated money to the Mariam Appeal, but he "never gave me a penny from an oil deal, a cake deal, a bread deal or from any other deal".
In December, Mr Galloway won £150,000 in libel damages from the Daily Telegraph over its separate claims he had received money from Saddam's regime.
Last month the newspaper won permission to appeal against the ruling to pay the damages, plus £1.2m in costs.