Donald Trump’s decision to withdraw all U.S. troops from Syria within 30 days was dumped Sunday, with National Security Adviser John Bolton effectively placing the exit on hold — possibly for years.

Speaking during a visit to Israel, Bolton introduced two new conditions for the U.S. troops withdrawal: The final defeat of Islamic State, and assurances from Turkey that U.S.-trained Kurdish fighters would be safe.

“The timetable flows from the policy decisions that we need to implement,” Bolton said in Jerusalem.

The Republican hawk, who joined the Trump administration last year, admitted that small pockets of Islamic State fighters remain in Syria and that a rapid withdrawal of U.S. troops could endanger its partners in the region. He also voiced concerns that Kurdish forces — seen by Turkey as a terrorist group — could be targeted by Ankara without Washington's protection.

The comments from Bolton, who travels to Turkey Tuesday for talks with President Recep Tayyip Erdogan, reverse Trump’s shock announcement on Dec. 19 that the U.S. was withdrawing from Syria because ISIS had been defeated.

”Our boys, our young women, our men, they’re all coming back and they’re coming back now. We won,” Trump said.

That decision led to the resignation of Defense Secretary James Mattis, who quit within hours of Trump’s statement. Mattis was followed this weekend by Pentagon Chief of Staff Kevin Sweeney, who announced he was returning to the private sector. A source told CNN the White House pushed Sweeney out.

Bolton’s visit to the Middle East is part of an effort by the Trump administration to reassure allies that the U.S. strategy on Syria had not shifted, despite what the president said. This followed weeks of grumbling from America’s partners in the region, most notably Israel, who expressed concerns that a sudden U.S. withdrawal would boost Iran’s growing influence.

“We can see John Bolton's visit as a way to correct or realign U.S. rhetoric with its actual policy,” Lina Khatib, head of the Middle East and North Africa programme at U.K.-based think tank Chatham House, told VICE News.

“Bolton has to double down on getting people to feel reassured that Trump's statement was an outlier and not a representation of a shift in U.S. policy.”

Secretary of State Mike Pompeo will also head to the region this week to similarly reassure allies about the continued U.S. effort against ISIS and Iran.

Bolton left the timeframe for a future withdrawal open-ended, meaning U.S. troops could be serving in Syria for months or even years.

Even Trump has admitted that 30 days is unrealistic, reportedly pushing the deadline out to four months just days after his initial announcement.

Asked about the shifting timeline from 30 days to indefinite as he departed the White House Sunday, Trump told reporters: “I never said we’re doing it that quickly.”

Trump isn’t the first leader to announce a troop withdrawal from Syria, only to quickly backpedal.

Russian President Vladimir Putin announced a similar draw down of Russia’s military presence in 2016 that never transpired.

“In this war, we have come to realize that announced deadlines don't necessarily transmit into reality,” Khatib said, noting that Washington and Moscow’s reluctance to leave is partly grounded in their desire to maintain a say in the outcome of the civil war and its aftermath.

“As long as the conflict in Syria continues to rage, whoever has military leverage on the ground, holds political cards in this conflict, so without military engagement, the U.S. will have given up its place at the table,” Khatib says.

But for all Bolton’s assurances, allies remain unsettled by Trump’s sudden foreign policy announcement — usually without the consultation of his top officials or allies.

“Given that Trump regularly contradicts his own leadership, most [partners] will likely wait until Trump himself confirms this latest change. And even then, he may still reverse course again, depending on what he watches on Fox News,” Karin von Hippel, the director general of the Royal United Services Institute, a defense and security think tank, told VICE News.