Special counsel Robert Mueller’s team has spoken with Blackwater founder Erik Prince, two sources familiar with the matter tell The Daily Beast. It was not immediately clear what questions Mueller’s team had or what information Prince shared with the special counsel.

Prince attended a now-controversial meeting with the head of Russia’s sovereign wealth fund in the Seychelles on Jan. 11, 2017—just over a week before Inauguration Day. The Washington Post reported that Mueller is interested in potential efforts at the Seychelles meeting to set up a backchannel between the Trump administration and the Kremlin.

A spokesman for the special counsel declined to comment.

Reached for comment, Prince spokesperson Marc Cohen did not dispute this reporting.

“Erik gave a full and frank public account of events as they concern him to the intelligence committee and he has nothing else to add on this topic,” Cohen said.

As Cohen noted, this isn’t the first time Prince has faced questions related to potential coordination between President Donald Trump’s campaign and the Kremlin. On Nov. 30, 2017, he spoke at length with the House intelligence committee about the campaign (PDF). The committee released the transcript of Prince’s interview, where he described his conversation with Russian Direct Investment Fund head Kirill Dmitriev. Prince told the committee that they discussed trade and terrorism.

“I met him at a hotel bar, and we chatted on topics ranging from oil and commodity prices to how much his country wished for resumption of normal trade relations with the—relationship with the USA,” Prince told the committee. “I remember telling him if Franklin Roosevelt could work with Josef Stalin to defeat Nazi fascism, then certainly Donald Trump could work with Vladimir Putin to defeat Islamic fascism.

“The meeting ended after a maximum of 30 minutes,” Prince continued. “I’ve had no communications or dealings with him or any of his colleagues before or after that encounter last January. That’s really all there is to say about that meeting.”

What Prince didn’t note was that Lebanese-American businessman George Nader also attended the meeting, according to the Post. The paper reported that Nader is now cooperating with the special counsel probe, and has met with investigators “numerous times.”

The Post reported last April that the meeting’s organizers were interested in discussing Persian Gulf politics.

“Though the full agenda remains unclear, the UAE agreed to broker the meeting in part to explore whether Russia could be persuaded to curtail its relationship with Iran, including in Syria, a Trump administration objective that would be likely to require major concessions to Moscow on U.S. sanctions,” the paper reported.

Prince is well-connected in Trump World. He donated $250,000 to pro-Trump efforts during the campaign, and his sister, Betsy DeVos, is Trump’s education secretary. Prince pushed hard—and unsuccessfully—for the administration to change its Afghanistan War strategy to rely on military contracting companies—the kind of firms that have made him a fortune. Prince is also close with former White House adviser Steve Bannon and has made numerous appearances on Breitbart’s radio show. But those relationships have not always resulted in Prince getting what he wants. Blackwater insiders have lambasted Attorney General Jeff Sessions to The Daily Beast (calling him a “big, giant wussy”) for the continued legal targeting of a Blackwater contractor over the killing of civilians in Iraq.

Prince also isn’t the only high-powered businessman in Mueller’s crosshairs. The New York Times reported last week that Mueller’s team has questioned Viktor Vekselberg, a Russian oligarch. Michael Avenatti, the lawyer for porn star Stormy Daniels, revealed on Tuesday that Trump’s lawyer, Michael Cohen, received a payment from a Vekselberg-linked company in the wake of the campaign. The Daily Beast confirmed Avenatti’s charge. And the AP reported that Mueller has also questioned Tom Barrack, a billionaire businessman who is close friends with the president.