Russia's Black Sea port of Novorossiysk, a key outlet for Russian commodity shipments, suspended oil exports on Friday after what authorities said was a major Ukrainian drone attack, two industry sources told Reuters.

The attack, one of the biggest on Russian oil-exporting infrastructure in recent months, comes after Ukraine in August stepped up strikes on Russian oil refineries in an attempt to degrade Moscow's ability to finance its war.

Long-range Ukrainian air and sea drone strikes have repeatedly disrupted Russian oil infrastructure this year, targeting Baltic and Black Sea ports, a trunk pipeline system, and a number of oil refineries.

Ukrainian President Volodymyr Zelenskyy said on Friday Kyiv had also fired long-range "Long Neptune" cruise missiles at targets in Russia overnight, adding that such strikes were getting more successful all the time. He mentioned no targets.

Russian pipeline oil monopoly Transneft has also been forced to suspend supplies to Novorossiysk, the sources told Reuters. The company declined to comment.

The Caspian Pipeline Consortium, which exports oil from Kazakhstan through a neighboring terminal, also suspended oil loadings until the drone alert is lifted.

Debris from the drones fell on the terrain of Russian grain terminal NKHP, which was working normally, Interfax news agency reported, citing director general Yury Medvedev.

Russian officials said Friday's attack had also damaged a docked ship, apartment buildings and an oil depot in Novorossiysk, injuring three of the vessel's crew members.

Global oil prices initially jumped by around 2% on supply fears after the attack, but recovered some ground and were up by less than 1% by 0815 GMT.

Delo, a transport and logistics group, said drone debris had fallen onto a container terminal in Novorossiysk, but that its operations continued as usual.

Crude oil shipments via Novorossiysk reached 3.22 million tonnes, or 761,000 barrels a day, in October, according to industry sources. For the first 10 months of the year, the figure was 24.716 million tonnes.

The sources told Reuters that a total of 1.794 million tonnes of oil products had been exported through Novorossiysk in October and that the figure from January until October totalled 16.783 million tonnes.

"Novorossiysk suffered the most," Veniamin Kondratyev, the governor of the Krasnodar region, where Novorossiysk is located, said on social media.

"Overnight, more than 170 people and 50 pieces of equipment dealt with the aftermath of the attack, quickly extinguishing fires and assisting residents," he said.

Three injured crew members of the damaged boat were being treated in hospital, said Kondratyev.

Local officials later said that a fire at an oil depot at the Sheskharis terminal, which handles crude oil and oil product exports, had been extinguished.

Coastal structures had also been damaged, they said, without providing details.

Reuters could not verify the accounts of the attacks and there was no immediate comment from Ukrainian officials.