Drones struck oilfields in Iraqi Kurdistan on Thursday, with officials pointing to Iran-backed militias as the likely source of attacks this week that have slashed the region's oil output by more than half.

The US on Wednesday condemned drone attacks on oil fields in the Iraqi Kurdish region. "The United States strongly condemns the drone attacks that have been targeting oil fields in the Iraqi Kurdistan Region since July 14,

Crude oil futures rise on supply concerns after drone attacks in Iraq's Kurdistan; market supported by lost production.