Any hopes a last minute compromise would allow the Mid-Antrim 150 races to go ahead have been snuffed out.
The organising club has upheld its decision originally made in December.
They say there are still major differences between the club and the Motor Cycle Union of Ireland.
T.T. star Adrian Archibald says it's a blow to his sport in Northern Ireland:-
Bumper turnout expected for Manx Two Day Trial
Solos and sidecars out across the Island this weekend
FC Isle of Man to begin new season on home soil
First six fixtures of 2026/27 campaign announced
Harrison wins fourth Southern 100 solo championship with new lap record
Kieran Clarke and Rob Coppock claim second sidecar title of the week
Harrison wins Southern 100 Senior Race
Five races conclude after opening session of Championship Day