Will Britain join the air strikes campaign against IS?

Speaking hours after a series of some 14 separate strikes were launched in Syria in a 90-minute operation, Mr Obama said that the action had been taken to disrupt the activities of the group and would be followed by moves to train and equip the Syrian opposition.

“It must be clear to anyone who would plot against America and try to do Americans harm that we will not tolerate safe havens for terrorists who threaten our people,” he said in his first comments since launching the strikes.

He added that the military action was taken with the support of Saudi Arabia, the United Arab Emirates, Jordan, Bahrain and Qatar. “This is not America’s fight alone,” he said, adding that “the people and governments in the Middle East are rejecting Isil [Islamic State] and standing up for the peace and security they deserve,” he said.

Mr Obama referred to addresses made earlier in the month when he prepared the ground for military action in Syria. He said that he had made clear that the US would “take action against targets in both Iraq and Syria so that these terrorists can’t find safe haven anywhere”.

He added: “I also made clear that America would act as part of a broad coalition. And that’s exactly what we have done.”

Mr Obama said that the strikes this morning were taken “to disrupt plotting against the United States and our allies by seasoned al-Qaeda operatives in Syria who are known as the Khorosan group”.

The group was named by US officials last week as being a new terrorist organisation, led by Osama bin Laden’s inner circle. The group was said to have been plotting against western targets.

Military hardware

American officials announced the strikes, which happened overnight, but Saudi Arabia, the United Arab Emirates, Jordan, Qatar and Bahrain were all involved in the operation in some capacity.

The Pentagon press secretary said that a mix of fighter, bomber and Tomahawk land attack missiles were being used against IS militants in Syria. In a statement officials said that there were 14 separate strikes, beginning after 1.30am GMT and lasting around 90 minutes.

A group monitoring the war in Syria said at least 20 Islamic State fighters were killed in the strikes, which were focused on IS headquarters and training centres in Raqqa city. The extremist Sunni Muslim group has seized large expanses of territory in Iraq and Syria and proclaimed a caliphate erasing borders in the heart of the Middle East.

Syrian state television said the US informed Syria’s UN representative on Monday that IS targets would be hit in Raqqa, which is 400 km (250 miles) north east of Damascus.

The US has already launched 190 strikes in Iraq, but this is the first time it has targeted IS in Syria after President Barack Obama announced his intention to do so a few weeks ago. Getting Arab allies on side was considered crucial to the American-led campaign and Secretary of State John Kerry travelled to New York at the weekend, ahead of the start of United Nations General Assembly meetings, to discuss plans on how to tackle IS with counterparts from Arab and European allies.

Several Arab states have powerful air forces, including Saudi Arabia and the United Arab Emirates. Saudi Arabia has also already agreed to host US training of Syrian opposition fighters. But many Gulf Arab states have been reluctant to be seen aggressively joining the US campaign, fearing in some cases reprisals by extremists or forces loyal to the Syrian government.

The strikes took place hours before President Obama goes to New York for the UN General Assembly where he will try to rally more nations behind his drive to aggressively take on Islamic State.