Brussels: US Defence Secretary Ash Carter said on Friday he expected both Saudi Arabia and the United Arab Emirates (UAE) to send special operations forces to Syria to help local opposition fighters in their drive to retake the city of Raqqa from IS.
Carter did not disclose how many commandos he expected them to deploy nor the timing of those deployments.
But he suggested they would play a major role taking back Raqqa, the IS's defacto capital, from the militants.
"We're going to try to give opportunities and power to... particularly Arabs in Syria who want to re-seize their territory back from IS, especially Raqqa," Carter told reporters travelling with him in Brussels.
Carter made the remarks after talks with his UAE and Saudi counterparts on Friday and Thursday respectively.
Four months of Russian air strikes in Syria have helped Syrian President Bashar Al Assad claw back territory from rebels fighting government forces.
Saudi Arabia had concentrated its military efforts over the last year on the conflict in Yemen, where it is leading a coalition battling Houthi fighters who control the capital, Sanaa.
Carter said on Thursday Saudi Arabia committed to expand its role in the air campaign and the United Arab Emirates said it would restart its participation.
Saudi Arabia and other Gulf countries took part on Thursday in the largest gathering so far of defence ministers from the US-led coalition against IS, which Carter hosted at NATO headquarters in Brussels.
Carter said the group collectively approved a campaign plan that aims to recapture the two main IS strongholds of Raqqa in Syria and Mosul in Iraq, as well as grappling with the group's spread beyond its self-declared caliphate.
That plan, however, does not include deployment of large-scale foreign ground forces to Iraq and Syria and Carter stressed that coalition commandos were meant to bolster local forces, not replace them.
"We're not looking to substitute for them, any more than we're looking to substitute for the Iraqi forces. But we are looking to enable them strongly and help them organise themselves," he said.
The United States has already deployed a small group of special operations forces to Syria and Carter said other allies, beyond Saudi Arabia and the United Arab Emirates, were considering commando deployments.
"Some don't even like to acknowledge the operations of special forces, but there are a number of them. And we are the organiser of them," Carter said.
Asked wheher the Saudis and UAE were already operating in Syria, Carter said: "No. They've had kind of liaisons there... We're talking about amping that up."