NEW YORK (REUTERS) - Oil prices have staged a stunning 40 per cent surge in three weeks, but charts show the rally could be near its end with crude prices approaching US$40 (S$55) a barrel, technical analysts said.

Oil has risen as much as US$11 a barrel since hitting 12-year lows of around US$26 for US crude and US$27 for global benchmark Brent.

Analysts said on Friday (March 4) that leaves them room to gain another US$2 to US$3.

"I'll really be surprised to see it go much higher than that without a major correction as US$40 is also a psychologically round number," said Mr Matthew Sferro, who studies technical charts for crude at New York's Informa Global Markets.

"What I really expect to see from here is choppy, sideways action," he added.

He based his target on the Jan 4 peak in oil markets before crude prices began an almost uninterrupted drop over a two-week span to reach 2003 lows.

Reuters charts show US crude at an intraday high of US$38.39 and Brent at US$38.99 on Jan 4.

On Friday, US crude settled at US$34.57, after scaling US$36.64. Brent closed at US$38.72 after a session peak at US$38.95.

Mr Sferro also cited resistance factors such as the 100-day moving average of US$38.95 breached by Brent on Friday and the Relative Strength Indicator (RSI) of above 60 for both crude grades as they approach the overbought RSI level of 70.

Mr Brian LaRose, technical analyst at ICAP in Jersey City, New Jersey, said oil's run up has presaged the seasonal springtime rally in crude.

Investors generally grow more bullish between mid-April and May, ahead of the peak US driving season. Going by the 12-year low of US$26.05 hit by US crude on Feb 11, Mr LaRose's average seasonal advance target of 41 per cent for the market put resistance at US$36.74.

"That's smack where we stand today on US crude," he said.