The Celtic League says the government is one of the weakest in living memory.
In an article to be published in the organisation's journal Carn, Bernard Moffatt says despite Tynwald members being elected on promises of renewal and transparency, it has delivered little more than drift.
In it, he calls for a directly elected Chief Minister, clear policy platforms, and full transparency in spending and performance.
And he also accused Tynwald members of looking after themselves with a backdated pay rise in 2023 while urging restraint on rises elsewhere.
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