Kurdish-led Syrian Democratic Forces (SDF) said on Monday that US forces were beginning to withdraw from positions in northeastern Syria on the border with Turkey, after Ankara announced it was planning a military offensive there.

"Despite our efforts to avoid any military escalation with Turkey, the US forces have not fulfilled their obligations and withdrew their forces from the border areas with Turkey," the SDF said in a statement.

"Turkey is now preparing an invasion of northern and eastern Syria," the statement said.

The White House had announced the withdrawal on Sunday night, saying that it would not "support or be involved" with planned Turkish military operations in the area.

US forces had backed and fought alongside the SDF in their fight against "Islamic State" (IS) fighters in the region, with Washington seeing the Kurdish-led force as the best ally in Syria to combat the extremists. The withdrawal is being seen by many Syrian Kurds as leaving them open to attacks by Turkey, which regards them with suspicion.

Offensive could come 'without warning'

The news comes following an announcement that Turkey would launch a military offensive in northeastern Syria. Turkish news agency DHA reported on Sunday that Turkish tanks and troops were already heading to the Turkish southeastern border area of Akcakale.

Turkish President Recep Tayyip Erdogan also confirmed that the US withdrawal had begun, saying on Monday morning that a Turkish military offensive in the area could begin at any moment. "We can come any night without warning," he told reporters.

Turkey sees Kurdish forces in the region as "terrorists" linked to a Kurdish insurgency at home and thus as a threat to its own security.

The region was declared a 'safe zone' by the US and Turkey and has been patrolled by the two sides

Trump: US 'only fights to win'

US President Donald Trump's decision to withdraw troops has been criticized not only by Syrian Kurds but also by some of Trump's closest allies in Congress, with Republican Senator Lindsey Graham calling the decision "a disaster" and "unnerving to its core." Top Senate Republican Mitch McConnell issued a statement say that the pullback would only benefit Russia, Iran and the regime of Syrian President Bashar Assad.

Lawmakers from both major parties have warned that clearing the way for a Turkish attack could lead to a massacre of the Kurds and send disconcerting signals to US allies across the world.

But Trump, who is in need of his party's support amid an ongoing impeachment inquiry, took to Twitter on Monday to explain his rationale, saying he had wanted to get out of Syria for the past three years. He accused Europe of frontloading its captured "Islamic State" (IS) fighters on the US and said the Kurds had been given a lot of money and equipment, noting that they had been fighting the Turkish state for a long time.

"It is time for us to get out of these ridiculous Endless Wars, many of them tribal, and bring our soldiers home. WE WILL FIGHT WHERE IT IS TO OUR BENEFIT, AND ONLY FIGHT TO WIN," Trump wrote.

"Turkey, Europe, Syria, Iran, Iraq, Russia and the Kurds will now have to figure the situation out," he added.

He later threatened to "destroy and obliterate" the Turkish economy if Ankara took any action he considered "off limits," saying he had taken such measures before, without giving details of which country was meant.

'Preparing for the worst'

In response to the news of the US pullout, the United Nations regional humanitarian coordinator for Syria, Panos Moumtzis, said: "We don't know what is going to happen," clarifying that the US had not notified the UN of the decision to withdraw in advance.

"We are preparing for the worst," said Moumtzis, adding that the UN already had a contingency plan in place to protect civilians in the area.

France, a main Washington ally in a US coaltion fighting IS in Syria and Iraq, also warned on the pullback, saying that the withdrawal and any action by Turkey could pave the way for a revival of IS in the region.

"We must be extremely vigilant that a maneuver of this kind can not, contrary to the goal of the coalition, strengthen" IS rather than eradicating it, said France's armed forces minister, Florence Parly.

Map showing the safe zone proposed by Turkish President Erdogan

No US support for Turkey

White House Press Secretary Stephanie Grisham said in a statement that the "United States Armed Forces will not support or be involved in the operation, and United States forces, having defeated the ISIS territorial 'Caliphate,' will no longer be in the immediate area." The statement employed the usual White House abbreviation for "Islamic State."

The White House statement came following a phone call between the Turkish president and his US counterpart.

NATO allies agreed on a safe zone in the region in August, but the US and Turkey are currently in disagreement about how far the zone should extend.

It is unclear whether the US will be completely withdrawing troops from all of Syria, as Trump announced in December.

Erdogan has been threatening to launch the offensive for months

Clearing 'terrorists'

Erdogan said following the phone call that the creation of a safe zone was "key to neutralizing the threat" of US-backed Kurdish militia in the region.

Turkish spokesman Ibrahim Kalin clarified in a tweet on Monday morning that the purpose of safe zone was to clear terrorist elements from the border and return refugees safely to Syria.

Turkey has previously said it wants to settle up to 2 million Syrian refugees in the zone.

A spokeswoman for German Chancellor Angela Merkel said on Monday that Germany is aware of the "special security policy situation" that Turkey faces on its border. Syrian Kurdish forces "must not be endangered," the spokeswoman stressed.

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tj,ed/ng (AFP, Reuters, dpa)

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