Michelle McIlveen was speaking after Fleur Anderson indicated that the criteria for when a vote would be triggered would be “based on opinion polls”.
Ms Anderson’s comments first appeared in an AgendaNI article at the weekend.
Ms McIlveen, the DUP’s deputy leader, said that a border poll is “divisive” and that “most people living here just want to make Northern Ireland work”.
She said Ms Anderson’s comments were “ill-considered”.
Parliamentary Under-Secretary of State Fleur Anderson with Secretary of State for Northern Ireland Hilary Benn.
Under the Good Friday Agreement, the power to call a border poll rests with the Secretary of State.
However, they have consistently refused to outline what exactly would be required.
On Sunday night, the NIO appeared to distance itself from Ms Anderson’s comments, saying “responsibility for a referendum sits solely with the Secretary of State”.
“This is clearly set out in the Northern Ireland Act 1998, which gives effect to the Good Friday Agreement and the principle of consent,” a spokesperson said.
“This has been — and remains — the only condition. The Secretary of State has been clear that there is no evidence that this condition has been met.”
It came on a weekend which saw Sinn Fein renew calls for a border poll by 2030.
Ms McIlveen said support for nationalist, pro-border poll parties has remained static since 1998.
“The combined support for the SDLP and Sinn Fein in 1998 was 39.6% and in 2022 was 38.1%,” she added.
“The suggestion by Minister Fleur Anderson that opinion polls could dictate the timing of a border poll is ill-judged.
“The Agreement makes clear that such a decision rests with the Secretary of State, based on clear evidence of a likely majority for constitutional change, not some haphazard opinion poll.
“That a Minister in His Majesty’s Government seems ambivalent and so uncertain about maintaining the Union is quite disgraceful.
“Last Friday, it was the Secretary of State who shared his irrelevant musings that we are ignorant of the law and how Northern Ireland is governed. Today, it’s the Minister of State. Collectively, the NIO Ministers need better counsel. They must do better.”
Fleur Anderson
The NIO has been contacted for comment on Ms McIlveen’s remarks.
The legislation states the Secretary of State should call a referendum on Irish unity “if it appears likely to him that a majority of those voting would express a wish that Northern Ireland should cease to be part of the UK and form part of united Ireland”.
Earlier this year, a LucidTalk poll published by the Belfast Telegraph showed that 48% of Northern Ireland voters want to stay in the UK, whilst 41% are in favour of constitutional change.
Michelle McIlveen
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In last year’s Westminster election, the total unionist vote was just over 43% while the nationalist vote was slightly over 40%.
The margins on the constitutional status have narrowed slightly, according to polls for this newspaper.
In a survey last year there was a 10-point gap between the two sides; with 49% supporting staying in the UK, while 39% wanted Irish unity.
In our most recent survey, 10% of people said they were unsure how they’d vote, while 1% would abstain or spoil their ballot.