Prices also were supported by indications that key OPEC members were acting on commitments to cut back production, in line with a decision earlier this month to take a daily 2.2 million barrels off the market.

Light, sweet crude for February delivery rose US$2.51 to US$40.22 a barrel in electronic trading on the New York Mercantile Exchange by afternoon in Europe. The contract on Friday rose $2.36 to settle at US$37.71.

In London, February Brent crude rose US$1.84 to US$40.21 a barrel on the ICE Futures exchange.

Escalating conflict

Israel expanded its air offensive against Gaza's Hamas rulers Sunday and prepared for a possible ground invasion. Arab leaders protested the attacks and Syria broke off indirect peace talks with the Jewish state.

With the two-day death toll nearing 300, Hamas fired rockets deeper than ever into Israel.

"There could be fear that an escalating Middle East conflict could disrupt supplies, though I don't see that happening at this point," said Gerard Rigby, energy analyst with Fuel First Consulting in Sydney. "(Israel-Palestinian conflict) always causes a bit of a blip and is one component that could support prices short-term."

In Vienna, JBC Energy, in its daily newsletter, said prices were also "supported by news that the UAE has decided to reduce crude supplies in January and February in line with the OPEC production cuts."

The United Arab Emirates are the fourth-largest producers in the 13-nation cartel.

Limits to recovery

But any recovery could have its limits. Oil prices have fallen 73 per cent since peaking at US $147.27 a barrel on July 11 as a credit crisis in the US sparked a steep drop-off in consumer demand and corporate earnings.

And analysts expect more dismal economic news from the fourth quarter over the next few weeks.

"More bad profit reports, jobs reports, housing results will put pressure on prices," Rigby said. "Once Obama comes in, that might start changing sentiment and generate more optimism."

Barack Obama is scheduled to be sworn in as US president on January 20.

Trading volumes have been low as many traders take off the week between Christmas and New Year's Day.

- AP