U.S. oil prices rose to within a few cents of a new 21-year record on Monday as traders and analysts expressed doubt as to whether Saudi Arabia's weekend pledge to raise oil output unilaterally would ultimately be enough to meet demand.

U.S. light crude futures rose 1.79 dollars to 41.72 dollars after climbing as high as 41.82 dollars at midday, just three cents off the contract's record price reached the previous Monday.

In London, internationally traded Brent crude was up 1.66 dollars to 38.17 dollars a barrel.

Saudi Arabia's Oil Minister, Ali al-Naimi, confirmed over the weekend that Riyadh was boosting output to 9.1 million barrels per day to meet demand next month. That would lift Saudi production by 10 percent from an estimated 8.3 million barrels per day in April.