* Oil extends rally into 4th straight session
* Renewed QE focus keeps dlr on defensive
* Cold spell in U.S., Europe offers price support
By Jennifer Tan
SINGAPORE, Dec 6 (Reuters) - Oil extended its rally into its fourth straight session on Monday, holding at 25-month highs, as the dollar languished at its lowest level in weeks, hit by weaker-than-expected U.S jobs data and a renewed focus on quantitative easing.
The market will take trading cues from more economic indicators later this week, with the Institute for Supply Management releasing its semi-annual economic forecasts for the U.S. manufacturing and services sectors on Tuesday.
Weekly U.S. mortgage data on Wednesday and jobless claims on Thursday will also be closely watched.
"Sentiment is very firm," said Peter McGuire, an independent market strategist based in Sydney.
"If the U.S. dollar comes under more fire, that's going to push crude prices higher. I wouldn't be surprised if the $91 and $92 levels were taken out later in the week."
U.S. crude futures for January <CLc1> was up 21 cents at $89.40 a barrel by 0250 GMT, off an earlier high of $89.60, its highest intraday since Oct. 9, 2008. The contract had settled at $89.19 on Friday, the highest close since Oct. 7, 2008.
ICE Brent for January <LCOc1> gained 23 cents to $91.65, after settling at $91.80 on Friday, just shy of a two-year high of $91.85 earlier.
Data on Friday showing the U.S. economy added fewer jobs than expected in November, driving the jobless rate to a seven-month peak, weighed on the greenback and boosted crude. [
]Putting the dollar further on the defensive, Fed Chairman Ben Bernanke said in a television programme later that the central bank could end up buying more than the $600 billion in U.S. government bonds it has committed to purchase if the economy failed to respond or unemployment stayed too high.
Oil and dollar-denominated commodities often move inversely to the dollar. A weaker dollar typically lifts oil prices as it lowers the value of greenbacks paid to producers, while making it less expensive for oil consumers using other currencies.
Also offering price support were plunging temperatures in Europe and colder weather in parts of the United States, which spurred demand for heating oil and other heating fuels.
The U.S. National Weather Service, in its eight to 14-day outlook issued on Thursday, called for below-normal temperatures for much of the eastern half of the country, which includes the world's largest regional market for heating oil.
The dollar eased 0.1 percent in early trade against a basket of major currencies , having fallen 1.4 percent last week. Against the yen, it stood at 82.82 yen , not far off a two-week low of 82.51 yen set last Friday.
U.S. stocks closed their best week in a month on Friday, shrugging off the tepid jobs growth in a sign that the rally may have further to run. (Reporting by Jennifer Tan; Editing by Ed Lane)