A GOP political consultant who admitted steering $50,000 from a Ukrainian politician to President Trump’s inaugural committee will face sentencing April 12, a judge ordered Wednesday, after signs that the committee is the subject of a deepening criminal investigation.

W. Samuel Patten, 47, agreed to cooperate with prosecutors after pleading guilty Sept. 1 to failing to register as a foreign lobbyist while working on behalf of a Ukrainian political party. That was the first public confirmation that illegal foreign money was used to help fund the January 2017 event.

U.S. District Judge Amy Berman Jackson set the April sentencing date after receiving sealed case updates Dec. 29 and Feb. 11 by prosecutors with the U.S. attorney’s office for the District of Columbia, which received the case on referral from special counsel Robert S. Mueller III.

Prosecutors’ willingness to move to sentence Patten may be a sign that their need of assistance from the former Republican campaign aide and foreign policy consultant is coming to a close.

As part of his plea deal, Patten agreed to assist the government. His cooperation included information about help he allegedly received from Konstantin Kilimnik, a Russian who prosecutors allege has ties to Russian intelligence and who also aided former Trump campaign chairman Paul Manafort in Manafort’s political consulting work in Ukraine.

Patten said in court documents that he arranged for an American citizen to act as a “straw donor” to give $50,000 in exchange for four tickets to Trump’s inauguration in place of a Ukrainian businessman, who as a foreigner was barred from contributing to the event.

On Feb. 4, federal prosecutors in Manhattan delivered a sweeping subpoena for documents related to donations and spending by the nonprofit inaugural committee, including all information related to donors, vendors, contractors, any foreign contributors and its bank accounts.

The nonprofit committee raised $100 million. Only U.S. citizens and legal residents can legally donate to a committee established to finance presidential inaugural festivities.

The subpoena indicated prosecutors are investigating crimes related to conspiracy to defraud the United States, mail fraud, false statements, wire fraud and money laundering.

Patten attorney Stuart A. Sears and a spokesman for the U.S. attorney’s office declined to comment beyond the information in the court docket.

Patten in his plea acknowledged forming a company with a Russian, identified as “Foreigner A” in court filings, whose description matches Kilimnik’s, to engage in lobbying and political consulting services. In a 2017 statement to The Washington Post, Kilimnik denied any connection to Russian intelligence and has not responded to recent requests for comment.

The company has received about $1 million since 2015 for its Ukraine consulting work, which included advising a Ukrainian party known as the Opposition Bloc, as well as some of its members, one of whom is a prominent Ukraine businessman identified only as “Foreigner B.”

The description of “Foreigner B” matches Serhiy Lovochkin, a Ukrainian businessman and politician who served as a top aide to former Ukrainian president Viktor Yanukovych, a pro-Russian politician who was Manafort’s chief client.

Patten told prosecutors that he worked with Kilimnik to help Lovochkin route the illegal donation to Trump’s inauguration. As a result of the donation, four tickets to Trump’s festivities were allocated to the three men and another Ukrainian; prosecutors said Lovochkin attended the event with Patten.

Lovochkin’s office has said he attended the inauguration but didn’t make the $50,000 payment.