Mariya Butina, who asked Trump and Putin to meet as a Russian agent

Ms. Butina saw N.R.A. as a powerful force for changing Republican politics, court records show. She described the group as "the biggest sponsor of the US congressional elections" and as a sponsor of the Conservative Political Action Conference. N.R.A. It is not mentioned in court records, but its links with Ms. Butina and Mr. Torshin have already been reported. N.R.A. did not reply to a message requesting a comment.

In May 2016, Mr. Torshin and Ms. Butina proposed a meeting between Mr. Trump and Mr. Putin during the annual meeting of the N.R.A. convention in Louisville, Ky. Jared Kushner, Mr. Trump's son-in-law, shot down the proposal. But Donald Trump Jr., the president's eldest son, met with Mr. Torshin and Ms. Butina at a dinner sponsored by N.R.A., although Mr. Trump's lawyer called the meeting briefing. Congressional investigators got a picture of the three people at the event, according to people close to the investigation.

According to prosecutors, a US political officer helped Ms. Butina identify political leaders, media and businesses. Ms. Butina met with the agent in Moscow, prosecutors said. Citing e-mails, prosecutors have presented the most explicit evidence so far that the Americans have knowingly helped the Russian effort of influence.

In an email, the American said that he had given Ms. Butina a map to find out how to proceed. "I and your friends in America can not make your life easier," wrote the political agent.

Butina and Mr. Torshin attended several events organized by Republican-affiliated groups, including two national prayer breakfasts in 2016 and 2017. In an email, Ms. Butina wrote that Mr. Torshin had suggested that Mr. Poutine attends the breakfast of February 2017, which Mr. Trump spoke about.

"President Putin did not say" no! "Ms. Butina wrote in the email.

Although the US agent is not identified, The New York Times has previously reported that Ms. Butina has developed a close relationship with Paul Erickson, a N.R.A. member and a long-time conservative activist who was part of the effort to arrange a meeting between Mr. Putin and Mr. Trump. Ms. Butina has publicly described the reception of Mr. Erickson during an event in Moscow. Mr. Erickson and his attorney did not respond to messages requesting comment. He is not identified in court records and has not been charged.

Butina also worked with a second unidentified American, prosecutors said.

After the November 2016 elections, Ms. Butina wrote to Mr. Torshin on Twitter, prosecutors said, "I'm ready for any other orders."