Aidan James was repeatedly rejected by the British army before setting out to join the fight against ISIL.

A British army reject who trained to fight against the Islamic State of Iraq and the Levant (ISIL or ISIS) could be facing a jail sentence on Thursday.

Aidan James, 28, from Formby, Merseyside, had no previous military knowledge when he set out to join the war in 2017, the Old Bailey heard.

Following a landmark trial, James, who was repeatedly turned down by British armed forces due to his mental health, was found guilty of training in weapons with the banned Marxist political organisation the PKK in Iraq.

But he was cleared of a second charge of training with Kurdish People’s Protection Units (YPG), across the border in Syria.

The defendant, who is in custody, will appear at the Old Bailey – the Central Criminal Court of England and Wales – before Justice Andrew Edis for sentencing.

It is the first time a Briton has been put on trial for going to Syria to oppose ISIL, after charges were dropped against ex-soldier James Matthews, 43, from Dalston, east London.

The court had heard how James was in contact with the antiterrorism programme Prevent before he left Britain for Iraq in August 2017.

While there, he wrote in his diary that sitting on a roof with a 0.50-calibre machinegun was like something out of “Mad Max”.

By December, he wrote that the situation with Turkey was worsening, saying: “Daesh [ISIL] is the biggest threat the world has seen since Hitler so anything I can do in these operations is good.”

Later, as he prepared to come home, James wrote in his diary of his “amazing time”.

He wrote: “Lost good friends, met great ones, fought on front line numerous times, killed Daesh soldiers, been shot at many times by Isis and our own guys.

“Drove humvys (sic), sat on roof as drove through desert, attacked by suicide vehicles many times, mortar fire, sniper RPG, drones, chilled with donkey.”

The court heard he finally returned to Liverpool John Lennon Airport on February 14 last year on flights via Baghdad, Amman and Amsterdam.

James declined to give evidence but denied training with the PKK in Makhmour, Iraq, on or before October 1, 2017, and attending another place for training in Syria with YPG units on or before November 4, 2017.