At a news conference Thursday, the two senators suggested the news that Syria may be preparing to use chemical weapons increases the stakes in the conflict there, ABC News reported.
"These reports may mean that the United States and our allies are facing the prospect of imminent use of weapons of mass destruction in Syria," McCain said. "This may be the last warning we get. We urge the President of the United States to make whatever military preparations necessary to show Assad that the United States is fully willing and able to impose the consequences that he has spoken of in the event that these weapons are used."
Lieberman, an independent who caucuses with Democrats, said the message from the news conference to Obama is: "We're with you."
"There is strong support across Congress if the president takes the strong action," Lieberman said.