Kurdish rebel forces in Syria announced have launched a campaign to retake the so-called Islamic State's Raqqa stronghold.
The US-backed group said they had set up command centre to coordinate with international coalition forces in a coordinated push to drive IS from their de facto 'capital' in Syria.
In a press conference hosted by umbrella rebel group the Syrian Democratic Forces, they urged residents to leave the city to avoid being caught up in fighting.
It comes as IS faces pressure in neighbouring Iraq under a major campaign to liberate the city of Mosul.
A Foreign Office spokeswoman told ITV News: “Ultimately, in order to defeat Daesh we are going to need to drive them out of Raqqa and Mosul.
"The Government of Iraq is making good progress in Mosul, and Daesh are being pushed back in Northern Syria, thanks to Turkey and other partners.
"It is right that the Coalition turn its attention to Raqqa. But we have always been clear that this is a fight that will take time and patience to get right and as the Foreign Secretary said in the House on Thursday 3 November, it would be premature to give a timetable for the isolation and eventual liberation of Raqqa.”