Russian Defence Minister Sergei Shoigu announced Wednesday plans to modernise anti-missile defence systems in the capital Moscow, after a series of Ukrainian drone attacks on Russian territory.

Several air defence systems have appeared on rooftops around Moscow this year.

"This year we will complete the modernisation of the anti-missile defence systems of the city of Moscow," Shoigu told army officials, cited by Russian news agencies.

He said that developing the air defence weapons was "one of the priorities" for the army.

Shoigu said the army would also form an "air defence division brigade that will be trained and equipped with new generation S-350 air-to-ground missile systems".

He did not say if these were new plans or if they were related to the conflict in Ukraine.

Drone attacks on Russian territory and on Moscow-annexed Crimea have increased in recent months, more than a year into the Kremlin's Ukraine offensive.

On Wednesday, authorities in Crimea claimed the Russian navy "repelled" a drone attack in the port of Sevastopol.

Last month, a drone attempted to strike a facility in the Moscow region.