British special forces are operating on the front line against the Islamic State of Iraq and the Levant in Syria, according to rebel commanders.

The Times reports that they have been defending a rebel unit against Isil attacks, marking the first evidence of the troop's direct involvement involvement inside Syria rather than training fighters in neighbouring Jordan.

First Lieutenant Mahmoud al-Saleh said British forces frequently crossed the border to help the New Syrian Army (NSA), comprised of former Syrian special forces, as it defends the south-eastern village of al-Tanf.

“They helped us with logistics, like building defences to make the bunkers safe,” he said.