(Bloomberg) -- Senator Lindsey Graham said the decision by President Donald Trump to withdraw U.S. forces from Syria “rattled the world” and must be reconsidered.

“There’s growing bipartisan support to ask the president to reverse course and to have a conditions-based withdrawal,” Graham of South Carolina, an ally of Trump’s who is influential on foreign policy, said Thursday at a bipartisan news conference in Washington. Graham said Trump’s decision “literally came out of left field.”

Graham was joined at the news conference by Senators Bob Menendez of New Jersey, the top Democrat on the Foreign Relations Committee, and Jack Reed, the top Democrat on the Armed Services panel.

Trump on Wednesday declared victory over the Islamic State terrorist group and ordered a withdrawal of U.S. forces from Syria in a sharp reversal of American policy that appeared to take the Pentagon by surprise and leave America’s Kurdish allies in the lurch.

“We have defeated ISIS in Syria, my only reason for being there during the Trump Presidency,” Trump said Wednesday morning on Twitter.

The announcement left key details unanswered -- such as a timetable for withdrawal, whether all troops would be pulled out and whether airstrikes would continue. U.S. lawmakers said the decision leaves Syria’s future in the hands of Moscow and Tehran, allies of President Bashar al-Assad whose intervention in the conflict averted his potential defeat in a conflict that started more than seven years ago.

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