Oil prices fell sharply during the week as growing concerns about weaker fuel demand in China outweighed worries that Russian supply could fall next month when tougher EU sanctions on its crude exports come into effect.
West Texas Intermediate, the US benchmark, was down about 10 percent this week and fell 1.9 percent on Friday to $80.08 a barrel. It was the biggest weekly loss since March.
Earlier in the day, US oil prices fell more than 4 percent to $78.50 a barrel, which…