Defense Secretary Jim Mattis downplayed reports that the Pentagon was considering deploying US ground combat troops to Iraq and Syria, but he didn't rule it out.
Asked about a CNN report that the Pentagon might propose sending US troops to expedite the fight against ISIS, Mattis said he was not "comfortable answering on my own at this point" on the troop recommendation.
"I first want to talk to the other allies and we'll decide where we're going," Mattis said from Brussels, after leading a defense-ministers meeting on the anti-ISIS campaign at NATO headquarters.
He said those discussions would begin soon.
"I'm going to fly from here into the Middle East," he said, according to Military.com. "Once we know what we have in a mutual appreciation of the situation, then we'll go forward."
The report that the Pentagon was weighing the recommendation to send group troops — which the Pentagon would neither confirm nor deny — would mark a significant shift in the US's role in fighting ISIS.
The US presence on the ground in Iraq and Syria has been limited to small special operations units, who are training and providing assistance to US allies fighting ISIS in those areas. US personnel were reportedly near the front lines in Mosul and have coordinated with the Kurdish YPG, a militia fighting ISIS in Syria.
Should conventional US forces be deployed to the region, they would require a much more significant security presence, both on the ground and in the air.
President Donald Trump, who directed Mattis to develop new options for defeating ISIS in late January, has also suggested the US could coordinate with Russian forces to combat the terrorist group.
Mattis has downplayed that possible alliance as well.
"We are not in a position right now to collaborate on a military level, but our political leaders will engage and try to find common ground or a way forward," Mattis said in response to questions about military cooperation with Russia at a NATO summit in Brussels.
More From Business Insider