World

US seeks Syria ceasefire, sanctions Turkey

By AAP Newswire

President Donald Trump has imposed sanctions on Turkey and demanded the NATO ally stop a military incursion in northeast Syria that is rapidly reshaping the battlefield of the world's deadliest ongoing war.

Trump, who gave what critics say was a de facto green light for Turkey's assault by ordering US forces away from the conflict area, requested the ceasefire in a call with President Tayyip Erdogan.

"The United States of America simply is not going to tolerate Turkey's invasion in Syria any further. We are calling on Turkey to stand down, end the violence and come to the negotiating table," Vice President Mike Pence told reporters on Monday.

Trump also announced plans to reimpose steel tariffs on Turkey and immediately halt negotiations on a $US100 billion ($A148 billion) trade deal.

The move was quickly criticised as too little, too late by the top Democrat in Congress.

"His announcement of a package of sanctions against Turkey falls very short of reversing that humanitarian disaster," said US House of Representatives Speaker Nancy Pelosi.

Turkey aims to neutralise the Kurdish YPG militia, the main element of Washington's Kurdish-led ally, the Syrian Democratic Forces (SDF), which has been a key US ally in dismantling the jihadist "caliphate" set up by Islamic State militants in Syria.

Ankara regards the YPG as a terrorist group aligned with Kurdish insurgents in Turkey.

Russia-backed Syrian forces on Monday took rapid advantage of the abrupt US retreat in Syria to deploy deep inside territory held by US-backed Kurdish forces south of the Turkish frontier.

Washington had announced plans for a full withdrawal from northern Syria less than 24 hours earlier.

Washington's Kurdish former allies said they invited in the government troops as an emergency step to help fend off the Turkish assault, launched on Wednesday after what the Kurds called a US betrayal.

The Syrian army deployment is a victory for President Bashar al-Assad and his most powerful ally, Russia, giving them a foothold in the biggest remaining swath of the country that had been beyond their grasp.

They will now face Turkish armed forces along a new front line hundreds of kilometres long.

Washington said on Sunday it was pulling out its entire force of 1,000 troops, which had provided air support, ground assistance and training for Syrian Kurds against Islamic State since 2014.

Trump said US troops would remain at a small garrison at Tanf in southern Syria "to continue to disrupt remnants" of Islamic State. But the base would do little to support operations elsewhere in the country.

Republican Senate Majority Leader Mitch McConnell, better known for his backing of Trump, joined his critics to express concern over the Syria pullout, saying it would "invite the resurgence" of Islamic State.

The fighting has raised concerns that the Kurds would be unable to keep thousands of Islamic State fighters in jail and tens of thousands of their family members in camps.

The region's Kurdish-led administration said 785 Islamic State-affiliated foreigners escaped a camp at Ain Issa over the weekend, but the British-based war monitor Syrian Observatory for Human Rights, citing sources in the camp, said the number who escaped was around 100.

EU countries have threatened to impose sanctions on Turkey over the assault. But at a meeting on Monday, they agreed not to impose an embargo.

US Defence Secretary Mark Esper said he would call on NATO allies to "take collective and individual" actions against Turkey when he meets defence chiefs in Brussels next week.