Washington CNN  — 

Maria Butina, the recently indicted Russian national accused of being an agent of Russia, told the Senate Intelligence Committee earlier this year that Russian billionaire Konstantin Nikolaev had backed her financially, a source familiar with her testimony told CNN.

Butina made international headlines last week when the Justice Department announced her arrest and a grand jury formally approved charges of conspiracy and acting as a foreign agent. The federal case has added to a growing picture of undisclosed foreign attempts to lobby in the US and alleged Russian influence in the political system.

Nikolaev’s office told CNN in an email Monday that he did provide some funding to a pro-gun organization run by Butina called Right to Bear Arms, but has not been in touch with her since 2014.

“Mr. Nikolaev has had no contact with Ms. Butina or her organisation since 2014,” his office said in a message in English. “He briefly provided some funding to the organisation from 2012 to 2014 specifically to support their efforts in Russia to raise public awareness around certain domestic issues. His interest and support were strictly limited to that effort, and he has provided no support of any kind to them since that time.”

The Washington Post reported earlier than Nikolaev’s office said the billionaire had been in touch with Butina, but not that Nikolaev had given her organization money.

The charges against Butina came after she gained the attention of lawmakers investigating allegations of Russian interference in the 2016 election, and in April, she sat for eight hours of testimony to the Senate Intelligence Committee.

The Washington Post first reported on this element of Butina’s testimony. Additionally, Nikolaev’s son supported President Donald Trump’s candidacy in the 2016 election, the Post reported, citing a person familiar with his son’s activities, and Nikolaev himself was seen at the Trump International Hotel in Washington during Trump’s inauguration, the newspaper said, citing two people aware of his presence.

Butina, along with her mentor, Kremlin-linked banker Alexander 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.

Butina, a gun rights activist, founded a pro-gun group in Russia called Right to Bear Arms, which Butina told the Senate panel was the recipient of Nikolaev’s funding, a person familiar with her testimony told the Post.

Nikolaev was in contact with Butina as she launched the group between 2012 and 2014, a spokesman for the billionaire told the Post. The spokesman declined to confirm to the Post whether Nikolaev gave her financial support.

Robert Driscoll, Butina’s attorney, 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.”

CNN’s Sam Kiley and Emma Burrows in Moscow contributed to this report.