Ministerial meddling in museum exhibitions in Northern Ireland is like Eastern Bloc politics before the end of communism, it has been claimed.
Alternative views on the origins of the universe, Ulster Scots and the Orange Order could be given more prominence by curators, according to Culture Minister Nelson McCausland.
A source close to the minister accused museums chiefs of trying to "airbrush" history.
But Mark Taylor, director of the Museums Association, said it was not the Democratic Unionist's place to interfere.
"I have been working in museums over 20 years and I can't recall in the UK an example of such blatant political interference," he said.
"It probably happened in eastern Europe during the cold war but it is pretty unprecedented."
Mr McCausland wrote to the trustees of National Museums Northern Ireland (NMNI) saying he wants issues given consideration in the short term.
He asked how the Ulster Scots tradition could be recognised, the contribution of the Hamilton Montgomery Settlement, considered the most important event in Ulster Scots history, the Orange Order, the nationalist Ancient Order of Hibernians and alternative views of the beginnings of the universe.
However supporters stressed he was not being prescriptive and accused museum organisers of leaving out part of Northern Ireland's history like the Orange Order.
Mr Taylor said curators had the expertise to decide on their exhibitions and accused the minister of driving a coach and horses through the principle that ministers keep away from decisions about programmes.