Turkish troops have begun an offensive in north-eastern Syria, which could lead to direct conflict with Kurdish-led forces allied to the United States.

Turkey's President Recep Tayyip Erdogan said the operation was to create a "safe zone" cleared of Kurdish militias which will also house Syrian refugees.

According to the Kurdish-led Syrian Democratic Forces (SDF), civilian areas were attacked by Turkish warplanes.

President Donald Trump controversially withdrew US troops from northern Syria.

His decision to pull back US soldiers from posts near two border towns after a phone call with President Erdogan at the weekend sparked widespread criticism at home and abroad.

The Kurds - key US allies in defeating the jihadist group Islamic State (IS) in Syria - guard thousands of IS fighters and their relatives in prisons and camps in areas under their control and it is unclear whether they will continue to be safely detained.

BBC