A Ukrainian drone has struck a Russian warship in the Gulf of Finland, forcing it to return to port.

The Security Service of Ukraine (SBU) said on Thursday it had targeted the Naro-Fominsk during a drone operation against a Kremlin oil depot in the Baltic Sea.

It marks the first time a Ukrainian drone has attacked a Russian ship in an area of the Baltic Sea which is used for civilian maritime traffic.

Helsinki’s defence ministry confirmed that the attack came in the early hours of Wednesday near Suursaari, about 28 miles from Finland’s coast.

A spokesman said: “The Finnish Defence Forces detected… a strike on a Russian warship in ‌the Gulf ‌of Finland ⁠area and has monitored the development of the situation.”

Finland ⁠is not under any immediate military threat, they added.

The strikes come as Steve Witkoff and Jared Kushner, both US envoys, held peace talks with Vladimir Putin in Moscow on Thursday before flying to Dublin for talks with Volodymyr Zelensky.

Following the talks Ukraine’s president welcomed a pledge to include European delegates in the next round of peace talks.

Kyiv has expanded its attacks in recent months on Russian oil infrastructure, despite the White House demanding a stop to strikes on energy sites.

Ukraine said the strike was part of a broader operation against Russia’s Primorsk and Ust-Luga oil ports.

‘Stable and safe’

Officials in Finland, a Nato member that has been one of Ukraine’s strongest allies in the war, said the incident was a direct result of Russia’s actions in the Baltic Sea.

The Gulf of Finland is a narrow arm of the Baltic Sea between Finland and Estonia that extends eastwards to St Petersburg.

Elina Valtonen, the Finnish foreign minister, insisted that the Baltic Sea remained stable and safe for civilian traffic.

The BBC reported that Finland’s defence officials had warned Ukraine that the Gulf – which lies between Finland, Russia and Estonia – has subsea cables and is a narrow waterway used by commercial ships and oil tankers.

Martin Herem, the Estonian defence minister, said the Ukrainian drone had entered Estonia’s airspace on Wednesday morning while Nato aircraft were in the air, but that it had not been safe for them to shoot down the drone.

“We know that smoke came from the ship afterwards,” he added. “The ship itself went back towards St Petersburg.”

The SBU said the Naro-Fominsk is an M-class small guided-missile corvette that was carrying Kalibr and Oniks cruise missiles.

The class of vessel is designed for shallow waterways, and is used by the Kremlin to protect its coastline.

There were also reports of Russian combat helicopters being destroyed.

Finnish media reported that Brig Gen Markku Viitasaari, from Finland’s defence ministry, confirmed at least one explosion on the ship.

Meanwhile, on Friday, Russia said that it had shot down nearly 1,200 Ukrainian drones across 15 Russian regions overnight, one of the largest swarms sent by Kyiv.

Four people working in an industrial zone, home to an oil refinery and a chemical factory, died in the southern Volgograd region, local authorities said.

Moscow also claimed that its forces had struck a cargo vessel ‌carrying ‌weapons ⁠and military ⁠equipment for Ukraine in the ‌Black Sea ‌southwest of Odesa ⁠overnight.