WASHINGTON - US President Barack Obama is expected to discuss the fight against the Islamic State (IS) militant group with US allies during an upcoming summit of Group of 20 economies, the White House said on Tuesday.

"It'd be impossible to travel all the way over there and not spend some time thinking about and talking about our ongoing effort to degrade and ultimately destroy ISIL," White House spokesman Josh Earnest said, using another acronym of IS.

"So I would anticipate that would be part of the President's visit," he said.

Leaders of the world's 20 biggest economies, including the United States, China, Japan, Russia, Canada, Australia and Brasil, are to meet next Sunday and Monday in the Turkish sea resort of Antalya to discuss global economic issues.

Many countries participating in the summit are also part of the US-led coalition against IS, Earnest added.

The US-led coalition has been bombing IS targets for more than a year.

Despite Obama's promise in the past that no US ground forces will be engaged in combat, the White House announced in October that it would deploy US ground troops to Syria, in a bid to assist rebels fighting the Islamic militants.

This will be the first time that US troops are deployed on the ground in Syria, where large swaths of territory have been controlled by the IS.

Washington is under increased pressure to have bigger involvement in fighting the IS in Syria, especially after Russia's military intervention in the war-torn country.