The small former Yugoslav republic of Montenegro on Friday ordered a Russian diplomat to leave over what it called violations of norms, prompting Moscow to promise a response.
Montenegro's foreign ministry announced the move on Twitter but gave no details. The Balkan nation has joined international sanctions against Russia over its invasion of Ukraine.
"Russia will give an appropriate answer," the Tass news agency cited a Russian foreign ministry spokesperson as saying when asked about possible retaliation.
In March and April, Montenegro's foreign ministry ordered a total of five Russian diplomats to leave over violations of diplomatic norms.
Tass said that in late May, Moscow had ordered a diplomat from Montenegro to leave Russia.
(Reporting by David Ljunggren; Editing by Paul Simao)
