Syrian war

Syria conflict: US presses Russia on military build-up

US Secretary of State John Kerry has called his Russian counterpart Sergei Lavrov in a bid to clarify the intent of Moscow's military build-up in Syria.

Mr Kerry warned that continued support for President Bashar al-Assad "risks exacerbating and extending the conflict," a statement said.

The US accuses Russia of boosting its military presence in Syria.Russia - Mr Assad's ally in the four-year civil war - says it is helping Syria fight Islamic State militants.

Moscow has increased its presence in the country just as the regime is losing ground to rebel groups.

Mr Kerry's phone call to the Russian foreign minister is believed to be his third in the past 10 days.