The rally, planned by An Dream Dearg – roughly translating to ‘the red group’ – is expected to attract thousands of people to “give voice to the widespread community demand for an Irish language act in the north”, according to the organisers.
An Dream Dearg describe themselves as “ an Irish language campaigning network”.
Sinn Fein are amongst those backing the rally.
Republic of Ireland Senator Niall Ó Donnghaile, a former lord mayor of Belfast, has invited members of the Irish Parliament to attend the rally.
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“Belfast is the beating heart of the Irish language revival,” he said.
People Before Profit MLA Gerry Carroll has also invited support for the rally, saying: “Change is very clearly on the horizon.”
Mr Allister, however, said those attending the rally are entitled to make their demands but that doesn’t mean there is “any merit” to them.
“Are they hoping the one per cent who can speak Irish will turn up?” he asked.
“Anyone is entitled to make a demand and to campaign for it but that doesn’t mean there is a merit to it. There is no merit to the demand for an Irish language act.”
The North Antrim MLA explained: “The Irish language is already feted in so many ways. It has its own cross-border body with full executive powers. It has its own special sector within education, publicly funded. It gets heaps of money every year from the public purse so there is no need for anything beyond that.”
He added: “The demand for an Irish language act is part of a political campaign to destabilise Northern Ireland, to seek to have Irish as an official language, to seek to have a preferment in the public sector and thereby discriminate against the rest of us, and to transform the public sector in Northern Ireland.
“It is a pernicious demand which is unwarranted, should not be met, and no one should be pandering to this demand.”
Turning his fire on the DUP, Mr Allister said: “The DUP have been slithering on the issue and are obviously preparing themselves to make huge concessions on it once the election is over.
“In their determination to get into government they are prepared to pay whatever price is required and that is wrong, it is foolhardy and it is something they should catch themselves on about.”
The DUP were invited to respond to Mr Allister’s comments but declined to do so.