President Donald Trump’s former national security adviser told an ex-business partner that economic sanctions against Russia would be “ripped up,” according to a whistleblower.

The new allegations against Michael Flynn ― who recently pleaded guilty to lying to the FBI about his contacts with Russia’s U.S. ambassador ― were made public on Wednesday in a letter from Elijah Cummings (D-Md.), a top-ranking member on the House Oversight and Government Reform Committee. Cummings said the whistleblower contacted him in June of this year with the new information. His letter was sent to Trey Gowdy (R-S.C.), who chairs the committee.

The whistleblower told Cummings he met with Alex Copson, managing partner of ACU Strategic Partners and a business partner of Flynn’s, on the day of Trump’s inauguration. It was just 11 minutes into Trump’s speech when Copson showed the whistleblower a text message from Flynn that discussed a joint partnership between the U.S. and Russia regarding the energy sector in the Middle East, according to the letter.

“During their conversation, Mr. Copson informed the whistleblower that he ‘just got this text message’ from General Flynn saying that the project was ‘good to go’ and directing Mr. Copson to contact their business colleagues to ‘let them know to put things in place’” the letter says.

Copson went on to say that “Mike has been putting everything in place,” according to the letter. “I am going to celebrate today. This is going to make a lot of very wealthy people.”

He then allegedly told the whistleblower that Flynn assured him economic sanctions placed on Russia by then-President Barack Obama ― in retaliation for Russian attempts to influence the 2016 election ― would be “ripped up.”

Cummings suggested that Gowdy subpoena the White House for documents the House committee requested in March, but which have not yet been provided, that might potentially corroborate the whistleblower’s account.

“I believe the American people want Congress to hold President Trump and his Administration accountable, and they are tired of Republicans in Congress putting their heads in the sand when faced with credible allegations of grave abuses while at the same time conducting investigations of allegations against Secretary Clinton that were debunked years ago,” Cummings wrote.