Mike Bloomberg’s presidential pollster has ended his years-long representation of a Ukrainian oligarch briefly scrutinized by U.S. law enforcement during its investigation into Russian election-meddling.

Pollster and pundit Doug Schoen told The Daily Beast on Tuesday that he has signed on to work on the former New York mayor’s 2020 Democratic presidential bid. In anticipation of that role, he said, he terminated a contract with billionaire investor Victor Pinchuk.

“As soon as Mayor Bloomberg made it clear that he would be formally announcing his candidacy,” Schoen said via text, “I terminated my professional relationship with Mr Pinchuk and filed the [Foreign Agents Registration Act] termination you referenced.”

Schoen’s work with Bloomberg predated his formal launch this past Sunday. An aide to the one-time mayor said that Schoen had done polling for them in anticipation of a presidential announcement in addition to his three successful mayoral runs.

Schoen did not answer directly when asked if he’d dropped any other clients in anticipation of Bloomberg’s White House run, or whether he felt that Pinchuk represented any unique political liability. “My central focus is and will be Mayor Bloomberg's campaign. And I am doing that happily, willingly, and with great enthusiasm,” he said. “Thank you very much for your questions.”

Schoen’s FARA filing, which he submitted to the Justice Department on Friday, disclosed about $324,000 in consulting fees and expenses paid by Pinchuk’s EastOne Group during the six months ending on October 31. Schoen was sure to note that he had informed DOJ that his contract with Pinchuk had ended before he was legally required to do so.

“Registrant wishes to proactively disclose that Registrant's representation of Victor Pinchuk terminated on November 6, 2019,” Schoen wrote.

The termination came eight years, almost to the day, after Schoen first registered to represent Pinchuk’s interests in the United States. Since then, the Ukrainian financer has turned up on the periphery of political disputes surrounding foreign meddling in the U.S. political process.

Special counsel Robert Mueller briefly probed Pinchuk’s 2015 payment to the Donald J. Trump Foundation for a televised speech that Trump gave at the Ukrainian’s annual Yalta European Strategy conference. Pinchuk was never accused of, or implicated in, any wrongdoing and he was not even mentioned in Mueller’s final report on the investigation.

Schoen, however, testified at the trial of lobbyist and former Obama White House lawyer Greg Craig over his belatedly disclosed work on behalf of a Russia-friendly Ukrainian political party in 2012. Schoen said that he had arranged for Craig’s work in the country alongside the imprisoned former Trump campaign chairman Paul Manafort. (Craig was acquitted of criminal charges earlier this year.) That work, Schoen said, was partially financed by Pinchuk.

Pinchuk’s name has also surfaced in the context of the ongoing impeachment inquiry against President Trump.

Two years after Trump’s 2015 speech, Rudy Giuliani, who now serves as the president’s personal attorney, traveled to Kyiv to address Pinchuk’s foundation. While there, he met with then-Ukrainian president Petro Poroshenko and a top prosecutor in the country, Yuriy Lutsenko, who peddled baseless conspiracy theories, subsequently relayed by Giuliani, at the center of the impeachment inquiry.

Schoen, for his part, has criticized Democrats’ determination to investigate Trump and possibly remove him from office.

“I have consistently argued that it would be a profound mistake for Democrats to be provoked into pursuing the impeachment of President Trump,” he wrote in a Fox News column two days before Mueller’s congressional testimony on his investigation—and two days before the Trump call with Ukraine’s president that eventually led to the impeachment inquiry. It is “clear that voters are tired of—and frankly, desensitized to—the continuous investigations of Trump, his presidential campaign and his administration,” Schoen claimed.

Pinchuk isn’t the only former client of Schoen’s whose work creates tantalizing and complicated political implications for Bloomberg’s run. Schoen also has done work for Trump himself, back when the president was in the real estate business and not electoral politics. Schoen advised Trump on a 150-story commercial and residential project that was to be dubbed “Trump City” but never actually materialized.

Reflecting on that venture this past year, Mark Penn—Schoen’s former polling partner—recalled that “Schoen had trouble collecting payment for his work, and had to settle largely for shuttle tickets that then became worthless.”

-- With reporting by Sam Stein