Kurdish forces secure last IS enclave in east Syria

US-backed fighters have seized the last Islamic State enclave in eastern Syria, with the jihadists surrendering, the Syrian Observatory for Human Rights says.

Children walk through the rubble of damaged buildings in the recently-liberated Harasta City, Syria. Source: EPA

The Syrian Observatory for Human Rights says US-backed fighters have seized the last Islamic State enclave in eastern Syria after the jihadists who were still there surrendered.

Reuters could not immediately confirm the report of Saturday's seizure.

The UK-based war monitoring group said the last few hundred Islamic State militants, many of them foreigners, had surrendered in the past two days to the Syrian Democratic Forces.

The final push against IS in Syria has begun, with the group losing all of its so-called caliphate. Source: AP

It said some militants may still be hiding in underground tunnels.

With the help of US air strikes, the Kurdish-led SDF has battled to crush Islamic State in the shrinking Baghouz enclave east of the Euphrates river near the Iraqi border.

'Large numbers' of civilians still in IS enclave: Kurd-led forces

"Large numbers" of civilians remain inside the last Islamic State group enclave in Syria prompting a fresh delay in a final advance, Kurdish-led forces said on Saturday.

Kurdish fighters standing guard at the site of a suicide attack near the town of Shaddadeh, in Syria's northeastern province of Hassakeh. Source: AP

"There are still civilians inside in large numbers," US-backed Syrian Democratic Forces spokesman Adnan Afrin told AFP on the day President Donald Trump said he expected to announce the end of the jihadists' "caliphate".

"We weren’t expecting this number, otherwise we wouldn’t have resumed the campaign four days ago. This is why it’s been delayed," Afrin said.