Russian Foreign Minister Sergei Lavrov has complained to his U.S. counterpart, Mike Pompeo, about the U.S. detention of Russian national Maria Butina on charges of conspiracy and acting as an unregistered foreign agent.
During a July 21 telephone conversation, Lavrov told Pompeo that Butina had been arrested on "fabricated charges" and called for her immediate release, according to a statement posted by the Russian Foreign Ministry.
Butina, 29, has been accused of attempting to infiltrate political groups, including the powerful National Rifle Association, to advance Russian interests. She is being held in Washington without bail.
"Lavrov emphasized that the steps of the U.S. administration, which arrested Russian citizen Butina in the United States based on fabricated charges, are unacceptable and that she should be released as soon as possible," the statement said.
According to the Foreign Ministry, the two ministers also discussed bilateral relations in the wake of the July 16 summit between U.S. President Donald Trump and Russian President Vladimir Putin.
The diplomats "exchanged opinions on the perspectives of the further development of relations between our countries with the goal of normalizing them on an equal and mutually beneficial basis," the statement said.
Relations between the two countries have been strained at least since Moscow's 2014 annexation of Ukraine's Crimea region. In response to that and to Russia's political, military, and economic support of a separatist campaign in parts of eastern Ukraine, the United States, the European Union, and others have imposed sanctions against Russia.
The Helsinki summit was the first meeting between the leaders of the two countries since then-presidents Barack Obama and Dmitry Medvedev met in Prague in 2010.
Lavrov and Pompeo also reportedly discussed the situations in Syria and in North Korea during their telephone conversation.
The Russian Foreign Ministry's statement said the July 21 conversation took place "at the initiative of the United States."