NATO is considering deploying battlegroups in Romania, Secretary General Jens Stoltenberg said in a joint press conference with the British Prime Minister Boris Johnson on Thursday.

"We are now studying the possibility of a long-term presence in the southeast of the alliance. Now we have battle groups in the Baltic countries and Poland. We are studying the possibility of deploying similar groups in the Black Sea region in Romania," Stoltenberg said.

Russian Foreign Minister Sergei Lavrov on Thursday said it was the sovereign right of any government to determine the length of military drills it chooses to hold, speaking after talks in Moscow with British Foreign Secretary Liz Truss.

Regarding Russia's joint drills with Belarus, the active phase of which began on Thursday, Lavrov said Russian troops always return to their bases after drills are completed.