Syrians use dirt to put out a fire at the scene of a reported air strike in the district of Jisr al-Shughur, in the Idlib province, on September 4, 2018.
CNN  — 

The Trump administration is walking back the notion of an imminent pullout of US forces from Syria, promising to remain until there is an “enduring defeat” of ISIS.

“This means we are not in a hurry to pull out,” said Ambassador Jim Jeffrey, the newly appointed US special representative, noting that creating conditions in Syria where ISIS or another terrorist group can’t return may take a while.

Jeffrey, a former US ambassador to Turkey, said the US was “shifting its position” to remain active in the country and to push for a complete withdrawal of all Iranian forces from Syrian territory.

Though President Donald Trump has previously expressed a desire to pull US forces out of Syria, Jeffrey said the President “is on board” with the new approach.

Jeffrey spoke to reporters as Russian forces prepare for an all-out assault on Syria’s Idlib province, the last rebel stronghold. Trump and his top officials have called attention to the impending Syrian government offensive in recent days, warning the Syrian regime and its backers Russia and Iran not to use chemical weapons or recklessly cause civilian deaths.

Jeffrey, who just returned from a trip to the Middle East and Turkey, called the situation in Idlib “very dangerous” and warned Syria and Russia against an assault.

“Any offensive is to us objectionable as a reckless escalation,” he said, adding that “there is lots of evidence that chemical weapons are being prepared.”

On Wednesday, Trump warned the Syrian regime that “the world is watching” and expressed concern about the 3 million civilians living there. His comments evoked past US warnings about Syrian military activities and the regime’s use of chemical weapons, which has previously triggered US military strikes against Syrian targets.

The US slapped sanctions on several companies with ties to the Assad government Thursday. In a statement, Treasury Secretary Steven Mnuchin said that “millions of innocent people in Idlib province are currently under the threat of imminent attack from the Assad regime, backed by Iran and Russia, under the pretense of targeting ISIS.”

An estimated 15 to 20 percent of the 60,000 to 70,000 Syrian rebels in Idlib are believed to be terrorists and Jeffrey said the US “asked repeatedly for permission” from the Russians to rid the area of the terrorists in order to avoid a mass assault. Turkey was also seeking to prevent a mass attack on Idlib at a summit among Russian-Iranian-Turkish leaders planned for Friday in Tehran.

With the campaign against ISIS winding down and Syrian leader Bashar al-Assad crushing the vast majority of his opposition, Jeffrey said it was time for a “major diplomatic offensive” in the weeks leading up to the United Nations General Assembly later this month. Jeffrey said the goal is to produce a political solution in Syria that stops the fighting and prevents conditions for a return of ISIS or another extremist group. He said Assad has “no future as a ruler” of Syria but that it was not Washington’s job to get rid of him.

Jeffrey said the new US approach is more suspicious of Russia amid “growing skepticism” that Moscow is either willing or capable of assisting the US with its goal of pushing “all Iranian-commanded forces from the entirety of Syria.”

“The consequences of that are that we will shift our positions and use all of our tools to make it clear that we’ll have to find ways to achieve our goals that are less reliant on the goodwill of the Russians,” Jeffrey said.