Syria: John Kerry arrives in London for Syria talks

US Secretary of State John Kerry has arrived in London where he is due to hold talks on the crisis in Syria.

Meanwhile, the Syrian president, Bashar al-Assad, has reportedly warned that Syria's allies would retaliate over any military action against his country.

In an interview with the US broadcaster PBS, Mr Assad is also said to have denied that he was behind chemical weapons attack in suburbs of Damascus on 21 August.

James Robbins reports.