U.S. Troops among 16 Dead in IS-Claimed Syria Bombing

A suicide attack killed U.S. servicemen in northern Syria Wednesday, causing the United States to suffer its worst combat losses in the war-torn country since 2014 as it prepares to withdraw.

The bombing claimed by the Islamic State group comes after U.S. President Donald Trump's shock announcement last month that he was ordering a full troop withdrawal from Syria because the jihadists had been "largely defeated."

The U.S.-led coalition fighting IS said "U.S. service members were killed during an explosion while conducting a routine patrol in Syria" Wednesday, without giving a death toll.

The Syrian Observatory for Human Rights said two Americans soldiers, nine Syrian civilians, and five U.S.-backed fighters were killed in the attack on a restaurant in the northern city of Manbij near the Turkish border.

Rubble littered the outside of the eatery in the city centre and its facade was blackened by the blast, footage from a Kurdish news agency showed.

According to Pentagon statistics, Wednesday's blast was the deadliest attack for U.S. coalition forces in Syria since they deployed in 2014.

The U.S. Department of Defense only reported two previous U.S. nationals being killed in combat in Syria, in two separate incidents.

The Britain-based Observatory, which relies on a network of sources in Syria, said it was the first such suicide attack in the city in 10 months.

- 'Security zone' -

Speaking at a gathering in Washington of U.S. ambassadors, Vice President Mike Pence did not comment on the attack and just said that the United States would ensure the defeat of IS, also known as ISIS.

"We'll stay in the region and we'll stay in the fight to ensure that ISIS does not rear its ugly head again," he said.

The bombing comes as Syrian Kurds present in areas around Manbij reject any Turkish presence in a planned "safe zone" to include Kurdish-held areas along the frontier.

Turkey has repeatedly threatened to attack Washington's Syrian Kurdish allies who Ankara views as "terrorists" on its southern flank.

Washington, which has relied heavily on the Kurds in its campaign against IS in Syria, has sought guarantees for their safety after Trump's pullout announcement.

On Tuesday, Turkey's President Recep Tayyip Erdogan said Ankara would set up a "security zone" in northern Syria following a suggestion by Trump.

But senior Kurdish political leader Aldar Khalil said any Turkish deployment in Kurdish-held areas was "unacceptable."

He said the Kurds would accept the deployment of U.N. forces along a separation line between Kurdish fighters and Turkish troops.

But "other choices are unacceptable as they infringe on the sovereignty of Syria and the sovereignty of our autonomous region," Khalil told AFP.

The Kurdish People's Protection Units (YPG) have been a key U.S. ally in the fight against IS.

They have taken heavy losses in a campaign now nearing its conclusion, with the jihadists confined to an ever-shrinking enclave of just 15 square kilometers (under six square miles).

But the jihadists have continued to claim attacks nationwide and abroad.

Ankara has welcomed Washington's planned withdrawal of some 2,000 U.S. troops from Syria, but the future of Kurdish fighters has poisoned relations between the NATO allies.

On Monday, Erdogan and Trump had a telephone conversation to ease tensions after the U.S. leader threatened to "devastate" Turkey's economy if Ankara attacked Kurdish forces in Syria, and called for a "safe zone."

- No 'outside interference' -

Erdogan said he and Trump had a "quite positive" conversation in which they spoke of "a 20-mile (30 kilometer) security zone along the Syrian border... set up by us."

The YPG-led forces fighting IS in a statement said they would provide "necessary support to set up the safe zone" -- if it came with international guarantees to "prevent any outside interference", in an apparent reference to Turkey.

The Turkish army has launched two major operations in Syria in recent years, with the latest seeing Turkish troops and their Syrian rebel allies seizing the northwestern enclave of Afrin from the Kurds last year.

Critics have accused Turkish troops and their proxies of military occupation of Syrian sovereign territory.

But while Ankara has spoken of a YPG-free "security zone" under its control, analyst Mutlu Civiroglu said it was not immediately clear what the U.S. president meant by a "safe zone," or who he thought would patrol it.

Analysts were "waiting for a clarification from Washington to see what the president really meant," he told AFP.

The U.S. planned withdrawal has sent the Kurds scrambling to seek a new ally in Damascus, which has long rejected Kurdish self-rule.

With military backing from Russia since 2015, Syria's regime has advanced against the jihadists and rebels, and now controls almost two-thirds of the country.

A northwestern enclave held by jihadists and pockets held by Turkish troops and their allies remain beyond its reach, along with the much larger Kurdish region.

On Wednesday, Russian Foreign Minister Sergei Lavrov said the Syrian government must take control of the north.