President Donald Trump said Monday he will make "major decisions" on Syria within 48 hours, and did not rule out new military action.

The president condemned reports of a chemical weapons attack that left dozens of people dead over the weekend, calling it "atrocious." He said "nothing's off the table" in response to the attack.

"Very concerned, when a thing like that can happen, this is about humanity," the president told reporters during a Cabinet meeting. "We're talking about humanity. And it can't be allowed to happen. So we'll be looking at that barbaric act and studying what's going on."

"If it's Russia, if it's Syria, if it's Iran, if it's all of them together, we'll figure it out and we'll know the answers quite soon," he added.

Later Monday, Trump said that the U.S. is "getting clarity" and "some pretty good answers" on who is responsible for the alleged chemical attack. The president did not provide further details on the subject.