The indictment alleges that Mr. Parnas recruited Mr. Sessions, then the chairman of the powerful House Rules Committee, to help try to oust Ms. Yovanovitch. At the same time, he and Mr. Fruman promised to help Mr. Sessions raise more than $20,000 for re-election.

In a letter last year to Secretary of State Mike Pompeo, Mr. Sessions accused Ms. Yovanovitch of disloyalty to the president.

Mr. Sessions lost his re-election bid, but announced this month that he was running for a different Texas congressional seat in 2020. He said Thursday that he knew nothing about the campaign finance scheme, and that he criticized the ambassador for one reason only: “I believe that political appointees should not be disparaging the president, especially while serving overseas.”

ANDREY KUKUSHKIN AND DAVID CORREIA

Both men were charged in the indictment, but not in connection with Ukraine. Rather, they were involved in the scheme with Mr. Parnas and Mr. Fruman to influence state and federal politicians to help get licenses for a recreational marijuana business. The business venture ultimately failed.

Born in Ukraine, Mr. Kukushkin, 46, is an American citizen living in the San Francisco area. Mr. Correia, 44, an American businessman, has described himself as an entrepreneur who works for a company that says it helps investors reduce the risk of fraud.

The influence-peddling scheme involved an unnamed foreigner with “Russian roots” who transferred $1 million “to cover all the donations” to federal candidates, as well as state candidates and politicians in Nevada, New York and elsewhere.

In Nevada, the men missed the application deadline but hoped officials would grant them a license anyway. They donated $10,000 to Wesley Karl Duncan, a Republican candidate running for attorney general in Nevada, who lost.