LONDON—Oil prices extended their gains on Friday at the end of a third volatile week of trade after slim progress in peace talks between Russia and Ukraine raised the specter of prolonged disruption to oil supply. Brent crude futures rose $1.14, or 1 percent, to $107.78 a barrel at 1003 GMT, after surging nearly 9 percent on Thursday in the largest percentage gain since mid-2020. U.S. West Texas Intermediate (WTI) crude futures climbed $1.24, or 1.2 percent, to $104.22 a barrel, adding to an 8 percent jump on Thursday. Both benchmark contracts were set to end the week down more than 4 percent, after having traded in a $16 range. Prices have dropped from 14-year highs hit nearly two weeks ago. The supply crunch from traders avoiding Russian barrels, stuttering nuclear talks with Iran, dwindling oil stockpiles and worries about a surge of COVID-19 cases in China hitting demand have …