A serving British soldier who left his army base to join Kurdish fighters battling against Isis has been found and is being returned to his unit, according to the Defence Secretary.

The unidentified solider, understood to be 19-years-old, left his base after telling his family he was joining Kurdish peshmerga fighters in their battle against the extremist group, saying: "these guys need our help."

Speaking during the regular Commons defence questions, Mr Fallon said: “The House may also want to know the soldier reported as missing last week has now been located and is being returned to his unit.”

When reports of the incident emerged last week, a Ministry of Defence spokesman confirmed that the situation was being investigated.

The soldier had joined the army as a 16-year-old after he left school, and had reportedly been learning Arabic.

"I've gone to join the Kurds in Syria and Iraq,” he wrote to his family, according to Sky News.

He continued that he was with other British people and a Canadian, adding: "I don't know how to explain it to you but I really want and need to do this and I will be safe."

The incident comes after it emerged last December that two former British soldiers travelled to Syria to fight against the group calling itself the Islamic State, which has claimed swathes of Syria and Iraq since last summer.

The pair said they felt "compelled" to take up arms following the murder of aid volunteer Alan Henning.

During the Commons defence questions, Mr Fallon was also asked to outline Britain's plans to tackle Isis.

Labour MP John Woodcock argued that it was troubling defence chiefs failed to outline the objectives for the campaign against Isis in recent evidence to a Commons committee.

Michael Fallon told the Commons: “Our plan in Iraq is very simple - it is to disrupt threats to the UK mainland and our interests overseas."

Referring the a US-led coalition against Isis, he continued: "Secondly it is as part of an international coalition to defeat Isil [Isis], including discrediting its violent ideology.

"It is thirdly to mitigate the impact of Isil and other violent extremist groups on the stability of the region as a whole."

Additional reporting by PA

Belfast Telegraph