Barack Obama
Barack ObamaReuters

The ISIS terrorist group is on the defensive, US President Barack Obama said, just days after a deadly shooting on a gay nightclub in Orlando which was claimed by the jihadist group.

Obama on Tuesday said the Islamic State group was losing ground in Iraq and Syria, and that the number of foreign fighters joining the extremists was plummeting.  

"ISIL lost nearly half of the populated territory it had in Iraq and it will lose more. ISIL continues to lose ground in Syria as well," Obama said after a meeting of the National Security Council on the fight against the jihadist group.

"In short, our coalition continues to be on offense. ISIL is on defense," Obama said, using an alternate acronym for the group.

A US-backed alliance of Kurdish and Arab fighters, fighting under the banner of the Syrian Democratic Forces, has been making steady gains against ISIS in northern Syria, and the group has also lost some ground to Syrian rebels and regime forces in that country - though it has struck back with deadly counter-attacks and suicide bombings.

In Iraq, pro-government forces are making slow gains in an operation to retake the city of Fallujah from ISIS, but have been hindered by stiff resistance. In northern Iraq, Kurdish forces have taken back large swathes of territory seized by ISIS in previous years, though their advances have largely ground to a halt in recent months.

ISIS has hit back in Iraq with deadly suicide bombings.

So-called Islamic State has attempted to claw back its declining legitimacy among potential recruits in spite of the losses, and analysts believe ISIS's recent calls for more terrorist attacks against westerners and western targets is an attempt to mask its battlefield losses and grant the group a sense of momentum despite them.

AFP contributed to this report.