Anti-IS offensive announces 'phase two' of Raqqa operation

A US-backed Arab-Kurdish alliance announced "phase two" of its campaign for the Islamic State group's Syrian bastion of Raqqa on Saturday, as Washington said it was sending 200 more troops to back the offensive.

The Syrian Democratic Forces will "begin phase two of the campaign, which aims to liberate territory west of Raqqa and isolate the city," SDF spokeswoman Jihan Sheikh Ahmed told reporters.

With a pre-war population of about 240,000, Raqqa is the de facto capital of the self-styled caliphate IS declared across Iraq and Syria in 2014.

Speaking in the village of Aaliyah, north of Raqqa, Ahmed said the SDF had captured 700 square kilometres (270 square miles) of territory since it began its advance on the city on November 5.

The alliance had also grown in size, she said, with more than 1,500 local fighters joining forces with the SDF after being "trained and equipped by the international coalition".

The SDF's coordination with the US-led coalition "will be stronger and more effective during the second phase of the campaign", Ahmed said.

Two SDF officials told AFP that US soldiers would take part in the offensive "on the front lines" alongside SDF fighters.

Earlier, the White House said it will deploy some 200 soldiers to assist in the global battle against the Islamic State group, as the coalition focuses its lens on Syria's Raqqa.

In a separate anti-IS assault, the Turkish army and its allies on Saturday entered the jihadists' northern Syrian stronghold of Al-Bab

Recapturing al-Bab

In a separate anti-IS assault, the Turkish army and its allies on Saturday entered the jihadists' northern Syrian stronghold of Al-Bab, a monitor said.

Backed by coalition air strikes, the SDF has pushed south from areas near the Turkish border, advancing to within 25 kilometres (15 miles) of the city.

But neighbouring Turkey has also since August pushed its own unprecedented offensive inside Syria against IS and Kurdish fighters.

On Saturday, Turkish troops entered the last bastion IS had in northern Aleppo province, the Observatory said.

Al-Bab had been under IS-control since 2014.

On Friday, Turkish media said Ankara was sending 300 commandos to reinforce its campaign inside Syria.

The anti-IS fight has been complicated by Turkey's deep hostility for the SDF.

Ankara regards the alliance's most powerful military component, the Kurdish People's Protection Units (YPG), as an arm of the outlawed Kurdistan Workers Party (PKK) that has waged an insurgency in Turkey for decades.

US defence officials said on Thursday they were brokering talks between Turkey and the SDF to prevent any further conflict between them disrupting the anti-IS campaign.

The battle for Raqqa coincides with a vast US-backed offensive to retake Iraq's second city of Mosul from the militants.