U.S.-backed militias said on Monday they had pushed IS militants out of the old quarters of Tabqa, a strategically vital town controlling Syria's largest dam, hemming the militants into the remaining modern district along the shore.

The Syrian Democratic Forces (SDF), an alliance made up of Syrian Kurdish and Arab fighting groups, are fighting a multi-phased campaign to drive IS from its stronghold of Raqqa, 40km (25 miles) downstream and east of Tabqa. 

The SDF will wait to assault Raqqa until it seizes Tabqa, its military officials have previously said, but it had made slow progress since besieging the town in early April.

This changed on Thursday when the SDF began to advance north into the old city.

On Monday the SDF said in an online statement it had taken the last three neighbourhoods of the old city and an adjoining industrial district.

SDF forces were now fighting IS in the three modern quarters of the town which lie along the Tabqa reservoir, SDF spokesman Talal Silo said.

IS still control the dam.

The Syrian Observatory for Human Rights, a Britain-based war monitor, said on Monday the SDF now controls about 80 per cent of Tabqa.

In recent weeks the SDF has also squeezed IS's pocket of territory around Raqqa.

Meanwhile, Russian Foreign Minister Sergei Lavrov and U.S. Secretary of State Rex Tillerson exchanged views on Syrian crisis talks scheduled for May 3-4 in Kazakhstan's capital Astana, the Russian Foreign Ministry said.

They also agreed to hold talks during an Arctic Council event in Fairbanks, Alaska, on May 10-11.

Source: Timesofoman