British intelligence agencies MI5 and MI6 have identified the man suspected of the horrific beheading of American journalist James Foley, according to British media reports.

The hooded man with an English accent is believed to be 23-year-old Abdel-Majed Abdel Bary, known to fellow Islamic State militants as Jihadi John.

The former rapper left his family home in an affluent west London suburb last year to fight in the civil war in Syria.