The attack targeted a DNO-operated oil field in Tawke, located in the Zakho area. A day earlier, the US-based Hunt Oil facility at the Ain Sifni oilfield in the Dohuk region was also attacked.
No group has claimed responsibility, but local officials cited by Reuters blamed Iran-backed Iraqi militias.
No casualties were reported in either incident but the attacks dented oil production by 140,000 to 150,000 barrels per day (bpd) according to two energy officials cited by the news agency. The region’s total oil output is reportedly around 280,000 bpd.
On July 13, Iraqi media reported that the United States warned Iraq it could face sanctions over alleged Iranian oil smuggling and ties to armed groups, including threats to freeze millions in revenue and target the state oil firm SOMO.
The United States opposes the presence of Iranian-backed armed groups in Iraq's security apparatus.
These militias, including Kata'ib Hezbollah and Asa'ib Ahl al-Haq, are part of the Popular Mobilization Forces (PMF) grouping which joined forces with the Iraqi military to confront Islamic State militants in Iraq.
Washington accuses them of receiving support from the Revolutionary Guard Corps-Quds Force to attack US personnel in Iraq.
Iran's armed allies in the region have been dealt heavy blows as a region-wide conflict between Israel and Iran has seethed.
The armed Houthi group in Yemen resumed attacks on the high seas following a June 24 ceasefire ending a 12-day war between Israel and Iran.
Houthi forces sank a Liberian-flagged carrier on July 6 with rockets and explosive drone boats. The group, which controls most of Yemen's population centers, says its maritime attacks are in solidarity with Palestinians in Gaza.
Yemeni forces fighting the Houthis carried out their largest ever seizure of advanced Iranian conventional weapons bound for the group, US Central Command (CENTCOM) said on Wednesday.