SINGAPORE/MOSCOW (Reuters) – Spot differentials for Russian ESPO Blend crude have edged to a record low in Asia as abundant supplies and low demand weigh on oil markets, several trade sources told Reuters on Monday.

A sudden plunge in global oil demand triggered by the coronavirus pandemic and widespread lockdowns has exacerbated supply issues in oil markets despite plans by the Organization of the Petroleum Exporting Countries (OPEC) and its allies to implement record output cuts in May and June.

Russia’s Surgutneftegaz sold three June-loading 740,000-barrel ESPO Blend crude cargoes to trading firm Gunvor in a spot tender awarded on Friday at wide discounts estimated from $4.60 a barrel to $5.00 a barrel to Dubai quotes, the sources said.

Gunvor purchased the cargoes for Chinese refiner Zhenhua Oil, they said. Some traders estimated that the two cargoes with later loading dates, June 9-16 and June 13-20, were bought at a weaker price level than the earlier cargo loading over June 6-13.

Trading house Paramount Energy also sold a June-loading ESPO cargo to Zhenhua Oil on Friday at a spot discount within the range achieved in Surgut’s tender, three of the sources said.

The price level on Friday was “a touch weaker than Thursday trades”, said one of the sources with direct knowledge of the trades.

On Thursday Surgut sold two June-loading ESPO crude oil cargoes at spot discounts of about $4.50-$4.60 and $4.75 a barrel to Dubai quotes, traders told Reuters.

Companies do not typically comment on such commercial matters.

High supplies of May-loading crude oil from Saudi Arabia to Asia planned for May, along with drastic falls in official selling prices, has pressured Russia’s ESPO Blend values, traders said.

ESPO crude is popular among Chinese independent refineries that collectively account for a fifth of the country’s crude imports.