Testimony to the US Congress by the head of a political research firm indicates that the Trump Organisation's sales of properties to Russian nationals may have involved money-laundering.
The House Intelligence Committee has released the transcript of a November 14 closed-door interview with Fusion GPS founder Glenn Simpson, whose firm hired a former British spy to research then-presidential candidate Donald Trump's campaign ties to Russia.
"Those transcripts reveal serious allegations that the Trump Organisation may have engaged in money laundering with Russian nationals," Representative Adam Schiff said.
The Trump Organisation dismissed the allegations as unsubstantiated.
Another Democrat on the Republican-controlled committee, Representative Jim Hines, sought to temper Schiff's comment, telling CNN that Simpson "did not provide evidence and I think that's an important point. He made allegations."
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The House of Representatives panel is conducting one of the three congressional investigations into possible collusion between Trump's 2016 campaign and Russia.
Special Counsel Robert Mueller is leading a separate probe by the US Justice Department.
Moscow denies the conclusions of U.S. intelligence agencies that it interfered in the 2016 election to help Trump and Trump denies any collusion.
In his testimony, Simpson said that his firm closely examined sales of condominiums in Trump properties in New York, Miami, Panama City and Toronto.
"There were a lot of real estate deals where you couldn't really tell who was buying the property," Simpson said. "And sometimes properties would be bought and sold, and they would be bought for one price and sold for a loss shortly thereafter, and it really didn't make sense to us."
"We saw patterns of buying and selling that we thought were suggestive of money-laundering," he continued.
Alan Garten, the Trump Organisation's chief counsel, said that the deals Simpson referenced primarily involve properties to which Trump licensed his name, rather than owning, developing or selling them.
"These accusations are completely reckless and unsubstantiated for a multitude of reasons," Garten said.
"These issues have nothing to do with the scope of the investigation" by the House intelligence committee, Garten said in a phone interview.
"But it's not surprising the minority (Democrats) would focus on this given they've found absolutely no evidence of collusion."
Simpson also said that Russia's operation to influence US politics included attempts to infiltrate the National Rifle Association and other conservative organisations, such as groups promoting independence for the states of Texas and California.
"They seem to have made a very concerted effort to get in with the NRA," Simpson said, according to the transcript.
