The autonomous Kurdish administration of northern Syria has confirmed they are seeking to return a British man with links to Isis in their custody over to UK authorities.

Jack Letts, known as ‘Jihadi Jack’ and now aged 21, left his hometown of Oxford for Syria in 2014, telling his parents he was going to Kuwait to study Arabic after converting to Islam and dropping out of school aged 18.

He was revealed to be the first white British man to be living in Isis’ so-called caliphate, although he denies he ever joined or fought on behalf of the militant organisation. Letts reportedly married while in Iraq and has a small child.

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In May 2017, as the US-backed fight to drive Isis out of Syria gained momentum, he was captured by the Kurdish People’s Protection Units (YPG) after leaving jihadist-controlled territory.

Sinem Mohamad, the Democratic Federation of Northern Syria (DFNS)’s European representative, confirmed in a statement on Monday that Letts was being held in the Rojava capital of Qamishli and local police are still investigating his case.

The Kurdish authorities intend to hand him over to the UK or Canada – where he also holds citizenship – once the investigation into his links to Isis has concluded, she said.

John Letts and Sally Lane arrive at the Old Bailey for a preliminary hearing, where they are accused of sending hundreds of pounds to their 21-year-old (PA)

“The outcome will be communicated to Jack's parents, and their legal representatives and to the officials of relevant governments,” Ms Mohamed said.

Letts’ parents maintain that their son is innocent. They have pleaded not guilty to charges of funding terrorism by sending cash to their son in an appeal due to be heard in the Supreme Court.

They have also accused the DFNS of holding Mr Letts in an “Guantanamo style black site” – an allegation that has been levelled at the conditions in Kurdish prisons several times.

“Isis brought inexplicable levels of terror on the peoples of Northern Syria/Rojava.

Syrian Democratic Forces take Raqqa from Isis – in pictures Show all 8 1 /8 Syrian Democratic Forces take Raqqa from Isis – in pictures Syrian Democratic Forces take Raqqa from Isis – in pictures Syrian Democratic Forces fighters celebrate victory in Raqqa atop of military vehicles REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Fighters of Syrian Democratic Forces march past destroyed buildings as they celebrate victory REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Fighters of Syrian Democratic Forces gesture the "V" sign in Raqqa REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Fighters of Syrian Democratic Forces evacuate a civilian from the stadium REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures A civilian prays after she was rescued by fighters of Syrian Democratic Forces from the stadium REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Syrian Democratic Forces fighters ride atop of military vehicles as they celebrate victory in Raqqa REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures Syrian Democratic Forces fighters celebrate victory in Raqqa REUTERS Syrian Democratic Forces take Raqqa from Isis – in pictures A fighter of Syrian Democratic Forces celebrates in Raqqa Reuters

“Despite this fact, the DFNS is not less committed than European countries to treating the fighters from this terror group according to international human rights standards,” Ms Mohamed said.

While the Foreign Office’s official position is that the government cannot assist British nationals in Syria, returning fighters pose a moral and legal headache for the UK authorities.

Last week, foreign office minister Rory Stewart said that it was in the UK’s interests for Isis fighters to be killed in Syria rather than return home.