Special counsel Robert Mueller is looking into foreign donations made to President Donald Trump's inauguration committee, according to a report Friday.
Mueller's team has questioned several donors with personal or business ties to Russia, Saudi Arabia, Qatar and the United Arab Emirates, ABC News reported.
Tom Barrack, a close Trump friend and real estate investor with deep ties to the Middle East, was interviewed by federal investigators working for Mueller last year, according to several reports.
Mueller is probing Russian election interference and potential connections between the Trump campaign and the Kremlin.
Barrack, who chaired Trump's inauguration committee, was grilled about Trump's former campaign chairman, Paul Manafort, and Manafort's onetime deputy, Rick Gates, The Associated Press reported.
Gates pleaded guilty to federal charges of conspiracy and lying in February, while Manafort, charged with bank fraud and other crimes, maintains his innocence.
Barrack was interviewed "months ago" and was asked a few questions about Gates' work on Trump's inaugural committee, one source told the news agency.
A second source told The AP that the questions were on a variety of topics, including financial dealings related to the Trump campaign, his transition and inauguration.
Investigators are also asking about specific donors, including Andrew Intrater, the CEO of investment firm Columbus Nova.
Intrater, who gave $250,000 to the inauguration, is a relative and close associate of Russian oligarch Viktor Vekselberg. Both men attended Trump's swearing-in ceremony.
Vekselberg, who has also been questioned by Mueller's team, was linked to embattled Trump lawyer Michael Cohen earlier this week in documents released by an attorney representing porn star Stormy Daniels.
The documents allege that Vekselberg steered $500,000 to a consulting firm run by Cohen through Columbus Nova.
Cohen used the consulting firm to pay Daniels, whose real name is Stephanie Clifford, $130,000 just ahead of the 2016 election to keep quiet about an alleged affair she had with Trump a decade earlier.
