A fire caused by lightning at Venezuela's 146,000-barrels-per-day El Palito refinery should be out later on Thursday and operations remain unaffected, a senior official at state oil company PDVSA said.

In the latest accident on the OPEC member's troubled oil installation network, an electrical storm set fire to two naphtha storage tanks at El Palito in centralVenezuela.

The incident revived painful memories of last month's disaster at Amuay, the South American country's biggest oil refinery, when a gas leak caused an explosion that killed 42 people, injured dozens and damaged 1,600 homes.

PDVSA's vice-president for refineries, Asdrubal Chavez, told state television the situation at El Palito was under control.

"We don't think this affects operations at all. Things are completely normal," he said.

"The fire is controlled in one of the tanks and confined in another. This afternoon we should have it extinguished."

The PDVSA official, a cousin of President Hugo Chavez, added that Venezuela's fuel inventories were at a "completely normal" level of 10-12 days. "There won't be any shortage problems."

Officials said the fire was some distance from production units at El Palito.

Last month's blast at the much bigger, 645,000-bpd Amuay refinery was the global oil industry's worst accident in years. Firefighters battled blazes in storage tanks there for days.

PDVSA has suffered a string of accidents and outages across its refinery network in recent years.

Critics say Chavez's socialist government is under-investing in the oil industry because it diverts so much crude revenue to welfare programs.