Oil company Saudi Aramco has told at ​least two European refining customers they will receive ‌no crude oil next month following an attack on Saudi Arabia’s key pipeline to the Red Sea, Bloomberg reported ​on Friday, citing people familiar with the matter.

European ​refiners typically buy Saudi crude under term contracts ⁠that guarantee monthly supplies, but Aramco has informed customers ​that next month’s deliveries will not proceed, the report said.

Saudi ​Arabia earlier informed European customers that some crude cargoes would be cancelled after drone attacks forced the shutdown of its East-West pipeline, ​damaging three pumping stations and disrupting oil loadings at ​the Red Sea port of Yanbu.

Read: Oil prices fall for third day on hopes of limited Saudi supply disruptions

The disruption has prompted customers, including Poland’s ‌Orlen, to seek alternative crude supplies, with traders saying the refiner bought North Sea grades to replace disrupted Saudi imports.

Reuters could not verify the report. Saudi Aramco did ​not immediately respond to ​a request ⁠for comment outside regular business hours.

Aramco is working to partially restart the pipeline within ​days and return it to full capacity ​within six ⁠weeks, Bloomberg reported, citing a person familiar with the matter.

Separately, Saudi Aramco has boosted crude exports from the Gulf through ⁠ship-to-ship ​transfers off Oman’s Sohar port ​to help offset volumes lost from reduced Red Sea shipments.