Oil fell below $43 a barrel on Friday as a resurgence of coronavirus cases raised concern that fuel demand growth could stall, although crude was still headed for a weekly gain on lower supply and wider signs of economic recovery.

The US reported more than 55,000 new coronavirus cases on Thursday, a new daily global record for the pandemic. The rise in cases suggested US jobs growth, which jumped in June, could suffer a setback.

"If this trend continues, oil demand in the region is at risk," said Louise Dickson of Rystad Energy.

Brent crude was down 56 cents, or 1.3%, at $42.58 a barrel by 1:52pm GMT, and US West Texas Intermediate (WTI) crude fell 58 cents, or 1.4%, to $40.07.

"The fragile US economic rebound is at risk of being undone by the latest surge in new infections," said Stephen Brennock of oil broker PVM.

Both benchmarks rose more than 2% on Thursday, buoyed by strong US June jobs figures and a drop in US crude inventories. Brent is still on track for a weekly gain of 5%.

Signs of economic recovery, and a drop in supply after a record supply cut by Opec and allies, known as Opec+, have helped Brent more than double from a 21-year low below $16 reached in April.

Boosting recovery hopes, a private survey showed on Friday that China's services sector expanded at the fastest pace in over a decade in June.

Opec oil production fell to its lowest in decades in June and Russian production has dropped to near its Opec+ target.

The bankruptcy filing of U.S. shale pioneer Chesapeake Energy also supported prices by raising expectations production will decline, JBC Energy said in a report.

Gasoline demand will be closely watched as the United States heads into the 4 July holiday weekend.