THE WIFE OF a British taxi driver who was captured by Islamic State militants says she has received a audio file in which he is pleading for his life.

In a statement released through the UK Foreign Office, Barbara Henning says that the audio file contains the voice of her husband Alan Henning who was seized when he volunteered to drive an ambulance full of medical supplies during an aid mission to Syria last December.

Henning makes a plea directly to the Islamic State group to asking them to “open dialogue”.

“I have seen Muslims across the globe question Islamic State over Alan’s fate. The voices of the people have spoke loud and clear,” she says.

He was working with Muslims to help the most vulnerable in Syria. Nothing has changed, he went to Syria to help his Muslim friends deliver much needed aid.We are at a loss to why those leading Islamic State cannot open their hearts and minds to the facts surrounding Alan’s imprisonment and why they continue to threaten his life.I have been told that he has been to a Sharia Court and found innocent of being a spy and declared to be no threat. I implore Islamic State to abide by the decisions of their own justice system.Please release Alan.

The Islamic State group, which now controls around one-third of Syria and Iraq, has killed thousands of people across both countries and has already beheaded two US journalists and a British aid worker. They have also threatened to kill another British journalist as well as Alan Henning.

The US began air strikes against IS in Iraq last month and today began an air assault on the group in Syria backed by five Arab states.

Read: Wife of British taxi driver captured by Islamic State pleads with captors to release him >