Exclusive-Russia's western oil exports hit 8-month high as drone strikes curb refining

June 2 (Reuters) - Russia boosted oil exports via its western ports by 15% in May from April, according to two industry sources familiar with the data, as refinery outages caused by Ukrainian drone attacks push Moscow to export more crude.

Ukraine has stepped up its drone attacks on both refinery and oil export facilities this spring, causing fuel shortages in Russia while also weighing on its oil production. Russia's oil output declined in April, the International Energy Agency said and Reuters reported.

May exports via the western ports of Primorsk, Ust-Luga and Novorossiysk rose to 2.5 million barrels per day from 2.2 million bpd in April, the sources said.

That is the largest amount exported from the western ports since September 2025, when Ukrainian drone attacks also suspended processing at Russian refineries.

Authorities have so far responded with an export ban on jet fuel and plans to curb exports of gasoline and diesel.

Higher crude oil exports are allowing Russia to avoid massive output cuts, sources said. However Russia's western export capacity is limited, making it difficult to accommodate all oil volume that hasn't been processed, they added.

Virtually all major oil refineries in central Russia have been forced to halt or scale back fuel output following Ukrainian drone attacks in recent days, according to official data and sources.

Exports rose in May despite ongoing drone attacks on Novorossiysk, which briefly suspended loadings. Ukraine also continued attacks on Transneft pipelines and pumping stations last month.

(Reporting by Reuters; Editing by Jan Harvey)