ISIS' leader in Iraq's Anbar province has been killed in a US-led strike, said a Pentagon spokesman on Monday.

Abu Waheeb died with three others when their vehicle was hit near the town of Rutba in western Iraq on May 6.

"ISIL leadership has been hit hard by coalition efforts and this is another example of that," said spokesman Peter Cook. "It is dangerous to be an ISIL leader in Iraq and Syria these days, and for good reason."

Abu Waheeb has been falsely reported dead a number of time before by Iraq media but this is the first time the Pentagon has confirmed his death.

The senior fighter was a former militant in Al-Qeada and has appeared in a number of ISIS execution videos, according to Cook.

The Anbar province in western Iraq has been largely controlled by ISIS since 2014. However coalition efforts have meant a number of towns have been recaptured including Ramadi and Hit.

Given his senior role Waheeb's death will hamper ISIS' ability to run operations in the province, said Cook.

"We view him as a significant leader in Isil leadership overall, not just in Anbar province," he said. "Removing him from the battlefield will be a significant step forward."

Waheeb was born in 1986 and was described as a rising star among ISIS ranks. The former computer science student was arrested by US forces in 2006 when he was a member of Al-Qaeda. However he escaped from in prison in 2012, according to the BBC.

Though US-led air strikes have taken out a numbe of ISIS members and some important leaders in recent months. However the group still controls much of its border-spanning "caliphate," and has inspired global affiliates. It has also shown it is able to orchestrate deadly external attacks like those that killed 32 people in Brussels on March 22.

Additional reporting from Reuters.