Russia's Foreign Minister Sergei Lavrov urged the "prompt release" of suspected Moscow agent Maria Butina during a conversation with US Secretary of State Mike Pompeo, the Russian Foreign Ministry said on Saturday.

Lavrov stressed "the unacceptability of the actions of the US authorities who arrested Russian citizen Maria Butina based on fabricated charges."

The 29-year-old Butina was detained in Washington, DC, last Sunday. Butina was a gun-rights advocate in Moscow before moving to the US as a graduate student at the American University, where she started a relationship with veteran Republican operative Paul Erickson and became a member of the pro-gun group NRA. She now faces charges of being part of a conspiracy to act as an agent for Moscow.

A US federal judge has decided to keep Butina jailed until her trial

During the phone call, Pompeo and Lavrov also discussed the goal of normalizing US-Russia relations on an "equal and mutually beneficial basis" and the issues surrounding Syria and North Korea. Russia's Foreign Ministry said the call was initiated by the American side.

'Some sort of comedy'

The fate of Butina seems to be connected with an ongoing effort to investigate the alleged Russian meddling into the 2016 election, which saw Donald Trump take office as US presdident.

Read more: Maria Butina - NRA member, lobbyist, and Kremlin agent?

Russia has repeatedly denied any wrongdoing. On Friday, Russia's ambassador to Washington, Anatoly Antonov, dismissed the case against Butina as a "farce" at an event in Moscow.

"This thing happening in the US with now is some sort of a farce, some sort of comedy," he said.

Antonov added that his embassy was trying to help Butina and help her release. He also said the Russian citizen was having a "hard time" while detained.

"There are attempts to prevent Russian diplomats from meeting this girl, basically [attempts] to break her," Antonov added.

dj/tj (AP, Reuters, Interfax)

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