Ali Harbi Ali, the man charged with murdering British Member of Parliament (MP) David Amess, considered himself affiliated with ISIS and had settled on a plan to kill a lawmaker years ago, a prosecutor said on Thursday.

"Ali considered himself affiliated to Islamic State (ISIS)," James Cable told a hearing at Westminster Magistrates Court, where Ali was making his first appearance after being charged earlier.

Ali, 25, was arrested at the scene of the killing in Leigh-on-Sea, east of London, last Friday and he also faces a separate charge of preparing acts of terrorism.

(Cover image: Police officers guard the scene where British MP David Amess was stabbed to death during a meeting with constituents at the Belfairs Methodist Church, in Leigh-on-Sea, Britain, October 16, 2021. /Reuters)