The Alliance Party are “the chief advocates for the anti-common-sense brigade”, Gavin Robinson has said.
The DUP party leader said: “They dismiss the values of many who are the backbone of our society.”
In a speech in Craigavon on Thursday night, he said the Alliance Party is “unrecognisable compared to their predecessors of 20 years ago.
“They have been captured by so-called progressives who now individually advocate for the destruction of Northern Ireland’s place within the United Kingdom and who stand shoulder to shoulder with Sinn Fein MLAs in the Assembly.”
In response, an Alliance Party spokesperson said: “Alliance is indeed a different force compared to 20 years ago.
“We are now the third-largest party and have a much greater platform to call out the damage being done to Northern Ireland’s economy, communities and environment by those who claim to be its great defenders.
“Our values and principles remain the same, unlike the DUP, who have none.”
Mr Robinson’s attack on the party came as part of a broader message about changing public attitudes.
He said that “throughout much of the Western world we have seen the steady advance of an ideology that dismisses common sense and brands anyone who questions it as extreme”.
He highlighted a current UK-wide trial of puberty blockers by researchers at King’s College London as an example.
Participation by people from Northern Ireland in it was paused by Health Minister Mike Nesbitt on Monday, after campaigners launched legal action against it.
The DUP had also raised objections to the trial, with Mr Robinson saying: “We did so not out of prejudice, but out of principle.”
“When others pressed ahead with pursuing this experimentation, we did not.”
He said the DUP’s intervention “forced the Ulster Unionist Party to confront reality and ultimately change course”.
In his speech Mr Robinson also repeatedly called for unity among unionists saying: “Division within unionism weakens our position and hands easy victories to our opponents.”
He dismissed those who “peddle the myth that a border poll is inevitable” but said a “pro-Union voting bloc” needs to be “built up”.
The DUP rejects “those within unionism who would attempt to manufacture division”, he added, warning: “When unionism fragments, our opponents advance. When unionism is distracted, others set the agenda.”
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