The US is expected to announce the deployment of US troops within Syria for the first time since the country's civil war began.

It is understood that under 50 special forces will aid moderate rebel groups in an advisory role, according to Reuters.

The US has already provided weapons and financial backing to rebel groups, but is now looking to strengthen its support while also looking for a diplomatic solution to the war which has engulfed the country since 2011, killing more than 250,000 people.

President Barack Obama has long attempted to avoid putting 'boots on the ground' and risking prolonged involvement in another Middle-eastern conflict. 

The decision comes as Russia has escalated its military role in Syria, conducting airstrikes against Islamic State and rebel targets.

An announcement is expected later today, as US Secretary of State John Kerry is currently attending talks in Vienna with foreign ministers from Russia, Iran, Saudi Arabia and Turkey.