The U.S. Justice Department on Monday charged a Russian national, Mariia Butina, with conspiring against the U.S. as a secret agent.

Butina and her mentor, Alexander Torshin, "took steps to develop relationships with American politicians in order to establish private, or as she called them, 'back channel' lines of communication," an FBI affidavit filed in court says, according to CNN.

"These lines could be used by the Russian Federation to penetrate the U.S. national decision-making apparatus to advance the agenda of the Russian Federation."

Leading up to the 2016 election, Butina sought to introduce Russians to Americans. She discussed posing as a go-between herself between powerful Americans and the Russian government.

She also suggested in September 2016 to two Americans that they should work to build "an advisers team on Russia for a new president."

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Following Donald Trump's election in 2016, she and Torshin discussed their predictions for secretary of state, and whether that was good for "our people," the affidavit said.

One of the Americans she worked with said one month before the 2016 presidential election they were working on a "VERY" private line of communication between the Kremlin and one political party through a gun rights organization, believed to be the National Rifle Association, according to court documents. Butina was involved with a Russian gun group that the National Rifle Association was supportive of and has met several Republican politicians, as evidenced in photos she took with them.

Butina and Torshin spent three years coaxing the Republican Party to be Russia's ally. They were preparing for when Obama and Putin would no longer be presidents.

"American society is broken in relation to Russia," she said in a Twitter direct message to Torshin in 2016. "This is now the dividing line of opinions, the crucial one in the election race. [The Republican Party] are for us, [the Democratic Party] against -- 50/50. Our move here is very important."

At one point in 2015, she and an American discussed a $125,000 budget for her "special project," to participate in major Republican conferences. The American told her she would have unlimited ability to meet American companies if she could be a potential intermediary to the Russian government, the complaint stated.

Later, following the 2016 presidential election, Butina and the Russian official discussed a possible pro-Russian conference that U.S. members of Congress could attend, according to the documents..

Butina allegedly raised the possibility that Russian President Vladimir Putin would attend the event in 2017. The demands: 15 world leaders at the breakfast, and a personal invitation from the President. The Prayer Breakfast organizer responded that he would provide 10 seats at the event. Putin did not attend.

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The case against a Russian agent infiltrating the Republican Party may be larger than just the one arrest.

Newly unsealed court documents show that prosecutors indicated in a court filing on Saturday their investigation into the Russian foreign agent had more than one subject.

This court filing has an overview of Russian influence efforts similar to that which Trump denied on Monday in Helsinki.

"Moscow seeks to create wedges that reduce trust and confidence in democratic processes, degrade democratization efforts, weaken US partnerships with European allies, undermine Western sanctions, encourage anti-US political views, and counter efforts to bring Ukraine and other former Soviet states into European institutions," the FBI wrote.

Torshin also reflected on their spycraft in a private Twitter exchange with Butina in 2016, according to the FBI. "It is not about winning today's fight (although we are striving for it) but to win the entire battle. This is the battle for the future, it cannot be lost!" he wrote, according to private messages published in court documents.

She responded that "harsh and impetuous moves will ruin everything early."

"Patience and cold blood + faith in yourself. And everything will definitely turn out," he wrote.

Butina has been in regular contact with Russian intelligence, the Justice Department says, and she attempted to offer sex in exchange for a position with an organization she targeted, according to NPR.

Prosecutors included that information in court documents as part of their request that Maria Butina be detained ahead of her trial because they say she is a "serious" flight risk.