Russia's Foreign Ministry has threatened to retaliate against U.S. diplomats if Washington enacts legislation restricting the movements of Russian diplomats in the United States.
Legislation now making its way through the U.S. Congress calls for tightening restrictions on Russian diplomats who want to travel more than 40 kilometers from their official posts in the United States. The diplomats would essentially be forced to get approval ahead of time from the FBI.
The bill would also create a new committee to counter what it calls Russian efforts to manipulate foreign opinion.
Foreign Ministry spokeswoman Maria Zakharova told a briefing in Moscow on December 7 that the legislation was part of a "witch-hunt" against Russia by outgoing President Barack Obama's administration.
"If the current U.S. authorities want to restrict the movements of Russia's representatives, then of course, it would merit keeping in mind diplomacy is based on the principle of reciprocity," Zakharova said. "Put simply, American diplomats in Russia will be treated in the same way."
"We are dealing with another example of clinical anti-Russian feeling," she added. "It's a carbon copy of a scheme used in the Cold War."
The proposed measure, which has passed the House of Representatives and both chambers' intelligence committees, is attached to a broader bill setting out policy priorities for the intelligence community. It has not yet been passed in the Senate.
The State Department has not publicly commented on the legislation. However, department officials have privately expressed misgivings about the restrictions and the consequences for the work of accredited U.S. diplomats in Russia, many of whom have reportedly been harassed by Russian security agencies.
Russia has also complained that its diplomats have been accosted or harassed by U.S. agents.
It's unclear whether the bill containing the Russian travel restrictions will pass the Senate or if Obama would sign such a bill into law.
President-elect Donald Trump, who will take office on January 20, would likely be less inclined than Obama to sign it if it ends up on his desk. Trump has repeatedly voiced a more conciliatory approach to relations with Russia that President Vladimir Putin has echoed.