Oil prices climbed on Friday, extending gains after OPEC+ said it would review supply additions ahead of its next scheduled meeting if the Omicron variant hits demand, but prices were still on course for a sixth week of declines. U.S. West Texas Intermediate (WTI) crude futures rose 27 cents, or 0.4%, to $66.77 a barrel at 0122 GMT, adding to a 1.4% gain on Thursday. However the producers left the door open to changing policy swiftly if demand suffered from measures to contain the spread of the Omicron coronavirus variant.