Alleged spy met with US officials in 2015

Butina attended meetings in 2015 with Stanley Fischer, then Federal Reserve vice chairman, and Nathan Sheets, who was then Treasury undersecretary for international affairs in the Obama administration. The meetings were first reported by Reuters.

The meetings were arranged by the Center for the National Interest, a think tank founded by former President Richard Nixon. Paul Saunders, the think tank's executive director, confirmed the meetings, but said that the Center for the National Interest did not invite Butina.

"We facilitated meetings for Alexander Torshin, in his capacity as a vice chairman of Russia's Central Bank," Saunders said in an email. "It was his decision that Maria Butina would accompany him as an interpreter."

Butina, along with her mentor, Torshin, worked for years to establish communications in the US for Russia, according to court filings and previous CNN reporting, and used the National Rifle Association as a major avenue of influence.

The Treasury meetings add to the list of known contacts that Butina made within the US government and with pro-gun politicians and advocates.

Butina's lawyer, Robert Driscoll, has not responded to CNN's requests for comment on the meetings. Driscoll has pushed back strongly on the accusations against Butina and told CNN on Friday that much of the US government's case against her was "taken completely out of context."

Ted Smith, a spokesman at PGIM, the investment management firm where Sheets works as chief economist, declined to comment on Sheets' behalf.

Fischer did not respond to CNN's request for comment Monday. He confirmed to Reuters that he met with Torshin and Butina, saying the conversation involved the "state of the Russian economy."

Saunders said that the think tank arranged the meetings for Torshin because he spoke at a seminar on Russia's banking sector in the think tank's offices, and the event included a career State Department official responsible for US-Russia relations.

"As a foreign policy think tank, the center routinely facilitates dialogue between the United States and other countries, including Russia," he said.

"We're a foreign policy think tank," Saunders added. "We talk to people in foreign countries and foreign governments all the time. That's what we do; it's what we're supposed to do. There's nothing at all inappropriate in that kind of activity. We don't take any money from Russia."

On Sunday, CNN reported that, according to a source familiar with her testimony, Butina had told the Senate Intelligence Committee earlier this year that she had received financial backing from Russian billionaire Konstantin Nikolaev.

Butina, a Russian national, founded a pro-gun group in Russia called Right to Bear Arms, which a person familiar with her testimony told The Washington Post received funding from Nikolaev.