Soldiers oversaw rationing of gasoline at service stations in several parts of Venezuela on Sunday as worsening fuel shortages forced angry drivers to wait for hours to fill their tanks, prompting protests in some areas.

Venezuela, whose economy is reeling from a painful five-year recession amid a prolonged political crisis, saw long lines of vehicles appear at services stations in several regions this week after a shutdown at the OPEC nation's second-largest refinery.

Shortages have been exacerbated by tough U.S. sanctions on Venezuelan state oil firm Petroleos de Venezuela SA (PDVSA) in January, which have slashed crude oil exports and imports of refined fuels.