The Russian Foreign Ministry issued a travel warning Thursday, saying that US intelligence services are on a "hunt" to detain Russian citizens traveling abroad.
In the statement, the ministry said the advice had been issued "in connection with the threat of being detained or arrested at the request of US law enforcement and intelligence services in third countries."
"Despite our calls to improve cooperation between the relevant US and Russian authorities... US special services have effectively continued 'a hunt' for Russians around the world," the statement said.
"Considering these circumstances, we strongly insist that Russian citizens carefully weigh up all the risks when planning trips abroad," it said.
Moscow and Washington have been engaged in a protracted diplomatic tit-for-tat amid allegations of Russian interference in the 2016 US presidential election. In late 2016, the Obama administration ordered the expulsion of 35 Russian diplomats from the United States.
Russian President Vladimir Putin hit back last year at American sanctions by ordering the US to cut staff at its diplomatic mission by several hundred personnel.
According to the statement issued Friday, more than 10 Russians have been detained in foreign countries at Washington's request since the beginning of 2017. The most high-profile Russian in American custody -- convicted arms dealer Viktor Bout -- was arrested in 2008 in Thailand and extradited to the US.
"After extradition to the United States, Russian citizens face a prejudiced attitude on the part of American 'justice,'" the statement said, describing Bout as a "Russian businessman."
The US has also issued its own travel warnings on Russia. On Jan. 10, a State Department travel advisory warned Americans to reconsider travel to Russia because of the threat of "terrorism and harassment."