A UK-trained naval officer has reportedly joined the Islamic State (Isil), raising fears he could use his knowledge of British maritime activity for terror attacks.

Ali Alosaimi, a 28-year-old Kuwaiti, spent three years training on a Merchant Navy officer's course in Britain before joining the jihadist group, according to the Mail on Sunday.

He reportedly trained at South Tyneside College’s Marine School in South Shields before heading to Syria and joining Isil in April 2014.

On an "entry form" the jihadist group uses to track foreign fighters, Alosaimi said he had been educated as a "navy officer in Britain".

Before coming to the UK he reportedly worked for a state-owned Kuwaiti oil tanker company.