Russia has repeatedly expressed concern over the US and NATO's escalating activity in the Black Sea, warning that it may result in unwanted incidents.

Russia scrambled its Il-114LL reconnaissance aircraft to shadow a US Air Force Boeing P-8A Poseidon surveillance plane over the Black Sea near Crimea, the Russian Telegram channel Voennyi Obozrevatel reports.

The reported incident is the latest in a series of such developments over the past several months that have seen Russian surveillance planes or fighter jets escort American spy planes over the Black Sea to prevent them from penetrating Russian air space.

The flights of Russian fighters were carried out in accordance with international rules for the use of airspace, with the country's state border remaining safe.

President Vladimir Putin earlier called them "destabilising" and "dangerous", while Foreign Minister Sergei Lavrov stressed that by sending ships to the area, the US is trying to push coastal countries toward confrontational policies.

As for the latest episode reportedly involving a P-8A Poseidon, it comes as NATO continues to beef up its military foothold in the Black Sea region amid Western media reports that Russia may be planning an "invasion" of Ukraine, allegations that Moscow rejects as unsubstantiated.