The US has carried out its first air strike against Islamic State (IS) militants under a new strategy to defeat the group.

The US military said Monday’s strike had destroyed an IS fighting position south-west of Baghdad that had been firing on Iraqi forces.

It came five days after US President Barack Obama outlined his plan to “degrade and ultimately destroy” IS.

The US has also been building a broad coalition to fight the group.

The jihadist group, also known as Isil or Isis, originated in Syria and has swept through parts of western and northern Iraq. It now controls large areas of both countries.

“The air strike south-west of Baghdad was the first taken as part of our expanded efforts beyond protecting our own people and humanitarian missions to hit Isil targets as Iraqi forces go on offence, as outlined in the president’s speech last Wednesday,” US Central Command said.

It also said an IS position near Sinjar in the north had been targeted on Sunday, destroying six IS vehicles.

The US has conducted more than 160 airstrikes across Iraq since August.

Previous US air strikes in Iraq have been carried out to protect US interests and personnel, help Iraqi refugees and secure infrastructure.

In a speech last week, President Obama unveiled a four-point plan to defeat IS using air strikes, material and technical support for ground troops, counter-terrorism activities and humanitarian help.

In another development, Iraq has criticised the decision not to invite Iran to Monday’s Paris summit on the IS threat.

Thirty countries pledged to join a US-led coalition against IS at the talks.

Foreign Minister Ibrahim al-Jaafari said the decision not to include Iran was “regrettable”.

“We believe that all world countries are concerned about the danger of terrorism,” he said.