A lobbyist who partnered with one of Paul Manafort’s key business associates has pleaded guilty to failing to register under the Foreign Agents Registration Act related to his political consulting work on behalf of a Ukrainian national.

Samuel Patten, 47 was charged and pleaded guilty Friday in the U.S. District Court for the District of Columbia.

The charge, brought by the U.S. Attorney’s office, stemmed from information uncovered by special counsel Robert S. Mueller III’s investigation into possible ties between the 2016 Trump campaign and Russia. Mueller referred the case to the D.C. U.S Attorney’s Office and Justice Department’s National Security Division.

Prosecutors alleged in the charging document filed in court Friday that Patten violated the law starting in January 2015 when he and “Foreigner A” began reaching out to members of Congress, White House officials, and media publications to set up meetings with his client, “Foreigner B.”

Prosecutors describe Foreigner A as a “Russian national” who partnered with Patten to create a political consulting company, “Company A,” split 50-50.

Foreigner A is believed to be Konstantin Kilimnik, Manafort’s co-defendant in a trial that kicks off next month in D.C. on similar charges to the one Patten faces.

Foreigner B, Kilimnik and Patten’s client, is a “prominent Ukraine oligarch.”

Patten’s Ukrainian and Russian clients paid his company $1 million through an offshore Cypriot account from 2015 to 2017, the charging document claims.

In January 2015, Patten and Kilimnik tried to coordinate meetings between his clients and lawmakers on the Senate Foreign Relations Committee and House Committee on Foreign Affairs, State Department officials, and multiple members of the U.S. press corps, prosecutors allege.

The charging document does not state whether Patten succeeded in setting up the meetings.

“The activity was undertaken to promote the interests of Foreigner B and the Opposition Bloc [of Ukraine] to influence United States policy,” according to the charging document.

Patten “knew at the time that he took all of the actions described” that he was supposed to register as a foreign agent, but that he failed to do so, prosecutors charge.

Patten and his Kilimnik even asked their client’s permission to register as foreign agents. But the Ukrainian oligarch said “in substance” that he did not want them to register at the time — perhaps later, according to the charge.

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