CVX's Venezuelan oil shipments halted by PDVSA amid payment uncertainty due to U.S. sanctions derails its plans to export oil.

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.

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.