Manx nationalists claim a decision to cut the number of grandstand seats for this year's Tynwald Day shows people are less interested in National Day.
In a post on Facebook, the Celtic League says a decline in people wanting to sit through the annual ceremony means the event is getting less attention from the public.
It claims photos from past events shows fewer people have been attending over the last decade.
And it accuses Tynwald Day of degenerating into what it calls "a cross between a medieval pageant and a funfair".
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