LONDON, Aug 13: IPE Brent crude futures surged by more than a dollar to yet more all-time highs after a US refinery blast and the prospect of a weekend referendum in key oil exporter Venezuela deepened concern about over stretched supply.

By 1705 GMT, September Brent crude futures were 83 cents higher at $43.12, down from a session high of $43.40, which was the highest level in the history of the IPE. US light sweet futures were up 50 cents at $46.00 a barrel, down from a new record high of $46.30.

IPE gas oil futures for September delivery settled $6.75 higher at $385. The dash higher on Friday came after an explosion at BP's 420,000 barrels per day (bpd) Whiting refinery in Indiana, which forced the closure of a hydro-treating unit.

Traders said the focus was also on Venezuela, which will hold a referendum on Sunday over President Hugo Chavez's rule. "With the Venezuelan referendum on the weekend, no one wants to go short," one dealer said.

In London, traders said Brent was also sustained by technical momentum ahead of Monday's front-month expiry and the front-month spread widened to around a dollar before closing in slightly.

Technical analysts predicted there could be a push towards the high $40s mark next week for US crude and possibly beyond to $50. Brent climbed well above initial resistance at Thursday's $42.56 high.

Oil prices have been on a seemingly inexorable climb as potential supply disturbances in Iraq, Russia and Venezuela have compounded worries that production will not keep pace with global demand, which is rising at the fastest rate in more than two decades.

Iraqi officials told Reuters on Friday that oil flows via the southern route were normal, but exports were running at half the Basra port's usual 1.7 million bpd. The oil industry in the Gulf of Mexico, where up to a third of daily 1.7 million bpd production was shut in due to Tropical Storm Bonnie, was slowly returning to normal. -Reuters