Russian oil producers have warned buyers they could declare force majeure on supplies from major Baltic Sea ports as Ukraine presses ahead with attacks on Russian energy infrastructure, two industry sources said on Friday.

Ukrainian President Volodymyr Zelenskiy told Reuters this week that Kyiv was using long-range strikes to maintain pressure on Russia after international oil sanctions on Moscow were eased due to global supply disruptions caused by the Iran war.

Ukrainian drones on Friday targeted the port in Ust-Luga, where a fire caused by a previous strike on Wednesday was still raging, the sources said.

Oil loadings at the port have been halted since Wednesday due to the raids, the sources said, adding that an official suspension notice from the Ust-Luga port authority did not give a timeline for a resumption of exports.

One of the sources said oil loadings from the Ust-Luga terminal may not resume until mid-April.

Primorsk, another major Russian Baltic Sea port, was also damaged during the recent attacks, though it partially resumed oil and fuel loadings on Thursday.

Alexander Drozdenko, the governor ‌of ⁠north-western Leningrad region where the two ports are located, said in a post on the Telegram messaging app on Friday that the region had been facing "unprecedented" drone attacks since March 22.

At least 40% of Russia's oil export capacity is at a standstill due to Ukrainian drone attacks, a disputed attack on a major pipeline and the seizure of tankers, according to Reuters calculations based on market data.

(Reuters)