Foreign minister’s comments come as his counterparts from the Baltic nations visit Kyiv in a show of solidarity.
The US State Department has branded as an “unprovoked escalation” reported Russian plans to block parts of the Black Sea, which could ultimately impact access to Ukrainian ports amid heightened tensions over Moscow’s military manoeuvres.
The US and its European allies have expressed concerns regarding Russia’s military build-up in recent weeks and fear Moscow might be planning to invade Ukraine. Russia, which backs separatists in eastern Ukraine, annexed Crimea in 2014.
Russian state media have reported that Moscow intends to close parts of the Black Sea to foreign military and official ships for six months, which could affect access to Ukrainian ports in the Sea of Azov, which is connected to the Black Sea through the Kerch Strait.
On Tuesday, more than 20 Russian warships took part in military exercises in the Black Sea, the Interfax news agency reported, citing a statement from Russia’s Black Sea fleet.
Russia has temporarily restricted the movement of foreign warships and what it called “other state ships” near Crimea.
“This represents yet another unprovoked escalation in Moscow’s ongoing campaign to undermine and destabilise Ukraine,” State Department spokesman Ned Price said in a statement.
“This development is particularly troubling amid credible reports of Russian troop buildup in occupied Crimea and around Ukraine’s borders, now at levels not seen since Russia’s invasion in 2014,” he added.
Last week, Washington slapped sanctions on Russia and expelled its ambassadors over Moscow’s interference in last year’s US presidential election, cyber-hacking, bullying Ukraine and other alleged “malign” actions.
Days later, Russia expelled US diplomats in a tit-for-tat move.
Ukraine and Russia have traded blame over a spike in violence in the conflict in eastern Ukraine, where Ukrainian troops have battled Russian-backed separatist forces in a conflict that Kyiv says has killed 14,000 people since 2014.
The US Federal Aviation Administration on Monday urged airlines to exercise “extreme caution” when flying near the Ukraine-Russian border, citing potential flight safety risks.
EU’s top diplomat Josep Borrell said on Monday that more than 100,000 Russian troops have amassed on Ukraine’s border and in annexed Crimea.
He said no new economic sanctions or expulsions of Russian diplomats were planned for the time being.
Ukrainian Foreign Minister Dmytro Kuleba, after addressing EU foreign ministers, called on the EU to impose new sanctions on Russia.