Russian President Vladimir Putin on Wednesday threatened to seize ships belonging to European countries in retaliation for plans to sell off cargo seized from Russian "shadow fleet" vessels.
Several European companies have intercepted ships carrying Russian oil in contravention of European sanctions targeting the vital revenue source.
New sanctions passed last month permit EU members to sell the oil or any other cargo seized from the ships.
Moscow has bristled at the moves, with Putin calling it "piracy and banditry".
"We will be forced to respond in kind," the Kremlin chief said while overseeing naval drills in Russia's Far East.
Moscow would act "wherever we ourselves deem necessary and appropriate -- anywhere," he added.
Swedish court documents obtained by AFP earlier in August showed Stockholm will transfer to Kyiv a seized Russian ship suspected of transporting grain from occupied Ukraine.
Putin was speaking aboard the Russian cruiser Varyag off the island of Sakhalin, where Russia's navy was conducting drills.
The exercises come a week before joint US-South Korean war games, designed to simulate a possible invasion from North Korea.
Tensions are high in the region amid accusations from Kyiv and Seoul that Pyongyang and Moscow are further intensifying their military cooperation.
