Multiple outlets have reported that Butina's plea deal includes an agreement to cooperate with investigators. CNN reported Wednesday, citing a person familiar with the case, that Butina has already offered information to investigators about an American she allegedly conspired with, as well as a Russian official alleged to have directed her U.S. activities.
Her violation carries a maximum sentence of five years in prison. A hearing was planned for February to discuss a date for sentencing.
Read Butina's plea deal with federal prosecutors here.
Butina was first charged by U.S. prosecutors in July. They alleged that she infiltrated U.S. organizations and cultivated relationships to advance a Russian agenda without registering as a foreign agent.
The 30-year-old purported gun rights activist came to the U.S. on a student visa in 2016, and allegedly worked to develop and "exploit" relationships with politically influential figures and organizations, including the NRA.
Butina had originally pleaded not guilty to prosecutors' charges. But her lawyers and federal prosecutors on Monday asked U.S. District Court Judge Tanya Chutkan for a hearing to change Butina's plea.
She has been in a northern Virginia jail since July, when prosecutors argued that she posed an "extreme risk of flight" because the charges against her also implicated "the activities of a senior Russian Federation official" who is believed to be Alexander Torshin, a close associate of Russian President Vladimir Putin.
The case is not directly linked to special counsel Robert Mueller, who is investigating Russian meddling in the 2016 U.S. presidential election, as well as possible obstruction of justice and potential collusion between Trump campaign-related figures and the Kremlin.
Court documents show Butina lived with a U.S. man in his 50s who has been identified as Paul Erickson, a Republican activist and NRA member. The Daily Beast reported last week that a lawyer for Erickson was sent a "target letter" informing him that prosecutors were considering charging Erickson with secretly acting as an agent for a foreign government. The letter also reportedly said prosecutors were weighing whether to charge him with conspiracy.
A spokeswoman for Russia's Foreign Ministry told CNN that Butina struck the plea deal "to survive," and suggested the arrest was politically motivated.
The Foreign Ministry had reacted to Butina's charges with outrage, launching a "Free Maria Butina" social media campaign and posting a photo of the alleged agent's face to the ministry's official Twitter account.
But Putin on Tuesday said that "nobody" at his country's spy agencies knows a thing about her.
"She risks 15 years in jail. For what?" Putin asked. "I asked all the heads of our intelligence services what is going on. Nobody knows anything about her."
Read the full plea deal below: