Venezuela's state oil company PDVSA has canceled several authorizations it had granted U.S.-based producer Chevron to load and export Venezuelan crude in April, three sources with knowledge of the decision said on Thursday.

This development comes after Washington cancelled key licences last month for several PDVSA partners including Chevron.

Chevron Corp. was ordered to return nearly 1 million barrels of Venezuelan oil to Petroleos de Venezuela SA in a blow to the oil major, which was working to secure crude before wrapping up operations in the country when a US sanctions deadline hits in May.