Russia also accuses the UK of helping Ukrainians in their attacks – a claim the UK dismisses as “false”.
Russia has accused Ukraine of carrying out a “massive” drone attack on the Black Sea Fleet in the Crimean port city of Sevastopol.
The attack began at 04:20 (01:20 GMT) and involved nine aerial and seven marine drones, Russian officials said.
At least one warship is said to have been damaged in the strikes. Ukraine has not yet acknowledged the incident.
Ukrainian troops have been successfully retaking territory occupied by Russians recently
Russia has replied by launching large-scale attacks on Ukrainian infrastructure, particularly on the country’s energy grid.
Mikhail Razvozhaev, the Russian-installed governor of the Sevastopol, said Russia’s navy had repelled the latest attack.
The strikes were the “most massive” on the city since Russia launched the invasion of Ukraine in February, Russian state media quoted the governor as saying.
He said that all unmanned aerial vehicles (UAV) had been shot down and no “civilian infrastructure” had been damaged.
At least one vessel sustained minor damage, the Russian Ministry of Defence said.
“In the course of repelling a terrorist attack on the outer roadstead of Sevastopol, the use of naval weapons and naval aviation of the Black Sea Fleet destroyed four marine unmanned vehicles, three more devices were destroyed on the internal roadstead,” a statement from the ministry read.
Russia also claimed the ships targeted on Saturday morning were involved in ensuring the “grain corridor” as part of the international initiative to export agricultural products from Ukrainian ports.
The agreement, brokered by the UN and Turkey, allowed Ukraine to resume its Black Sea grain exports, which had been blocked when Russia invaded the country. It was personally negotiated by the UN secretary general and celebrated as a major diplomatic victory that helped ease a global food crisis.
But Russia complains that its own exports are still hindered, and has previously suggested it might not renew the deal.
In recent days, Kyiv has accused Moscow of deliberately delaying the passage of ships, creating a queue of more than 170 vessels.
Sevastopol is the largest city in Crimea, which was annexed by Russia from Ukraine in 2014.
Russia’s Black Sea Fleet was previously targeted in April this year by Ukrainian forces when its flagship, the cruiser Moskva, was sunk. The 510-crew missile cruiser had led Russia’s naval assault on Ukraine, and its sinking was a major symbolic and military blow.
And in recent weeks, the fleet’s home in the Crimean peninsula has come under attack from Ukrainian forces.
Earlier this month, a blast occurred on the Crimean bridge – a pivotal symbol of Russia’s annexation of Crimea.
The blast killed three people, Russian investigators said.