(CNN) – Special counsel Robert Mueller's team questioned a Russian oligarch about payments to President Donald Trump's personal attorney, Michael Cohen.
This is one of the newest developments in Mueller's investigation into Russian dealings.
Viktor Vekselberg, the oligarch, is close to Russian President Vladimir Putin. Mueller asked him about hundreds of thousands of dollars in payments his company's U.S. affiliate made to Cohen after the election, according to a source familiar with the matter.
Last month, the Trump administration sanctioned him and others for activities including election interference.
Sources said investigators also asked Vekselberg about donations made by the head of his company's U.S. affiliate to Trump's inaugural and campaign funds.
The business relationship between Cohen and Vekselberg, as well as the purpose of those payments, are unclear.
But the investigation could add to Cohen's existing legal troubles.
Cohen's home and office were raided by the FBI last month.
According to court documents, prosecutors said at least part of that inquiry stemmed from a referral from Mueller's office.
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