By Colleen Howe and Siyi LiuBEIJING/SINGAPORE (Reuters) -Oil prices extended gains on Monday, rising more than $1 on a decision by OPEC+ to delay by a month plans to increase output, while the market braced for a week that spans a U.S. presidential election and a key meeting in China.Brent futures rose by $1.18 per barrel, or 1.61%, to stand at $74.28 a barrel by 0402 GMT. U.S. West Texas Intermediate (WTI) crude rose by $1.21 a barrel, or 1.74%, to stand at $70.70.On Sunday, OPEC+, which includes the Organization of the Petroleum Exporting Countries plus Russia and other allies, said it would extend its output cut of 2.2 million barrels per day (bpd) for another month in December, with an increase already delayed from October because of falling prices and weak demand.The grouping had been due to increase output by 180,000 bpd from December."While the delay until January does not change fundamentals significantly, it does potentially leave the market having to rethink the strategy of OPEC+," ING analysts said in a note.The delay bucked the expectations of some in the market for OPEC+ to deliver the planned hike in output, they added."This delayed supply increase means that maybe the group are more willing to support prices than many believe," they said.The group is set to gradually unwind the 2.2-million-bpd cut over the coming months, while another 3.66 million bpd of production cuts will stay until the end of 2025.Brent and WTI posted weekly declines last week of about 4% and 3%, respectively, as record U.S. output weighed on prices. But both contracts edged up on Friday on reports that Iran could launch a retaliatory strike on Israel within daysinvesting.com