Video is the trailer for a film entitled 'Flames of War' with strapline 'fighting has just begun'
The only words on the 52-second clip are those of President Obama making the pledge, "American combat troops will not be returning to fight in Iraq"
Islamic State militants have threatened to target the White House and kill US troops in a new slickly-made video response to Barack Obama's campaign to "degrade and destroy" the organization.
The video, in the style of a blockbuster movie trailer for what is "coming soon", depicts a masked man apparently about to shoot kneeling prisoners in the head. Towards the end of the clip there is shaky footage of the White House filmed from a moving vehicle, suggesting the building is being scoped out for attack.
It was released on Tuesday after US defence chiefs suggested that US troops could join Iraqi forces fighting Isis, despite Obama's assurance that US soldiers would not be engaged in fighting on the ground.
Video screen grab - White House
The video was released by the al-Hayat Media Centre, Isis's English-language propaganda arm. It includes the now familiar high-production hallmarks of an Isis video, including super-slow motion footage of jihadis in combat, jump-cutting, and CGI explosions.