A Democratic Unionist Party (DUP) The MP has said the party will not vote for Theresa May's Brexit agreement, even though she presents it to the House of Commons "thousand times".
The party's Brexit spokesman Sammy Wilson said his position was corrected.
He accused former Prime Minister Sir John Major and Justice Secretary David Gauke of "scare tactics".
They said Sunday that a no-deal Brexit could endanger Northern Ireland's place in Britain.
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Sir John told the BBC's The Andrew Marr Show: "I think a particular Brexit will pose a risk to the association with Scotland and over time the association with Northern Ireland."
"It's too high a price, and I think that's something Parliament should wear in my d."
Gauke said the Prime Minister's agreement was the "best result" and added: "Sometimes you have to accept your second or third choice to avoid a result you consider even worse. "
& # 39; Scared of Threats "
In his Eastern Antrim constituency Sunday evening, Wilson told BBC News NI:" Should bring it back a thousand times, we will vote against it because the consequences for Northern Ireland are far too serious.
"We have been determined."
"And therefore we are laughing at these kinds of threats that we get from John Major and David Gauke today."
He said that May's withdrawal agreement, if adopted, could create a trade barrier between Northern Ireland and Britain and "destroy the association".
"Our message to the prime minister is: do what you should have done in the beginning and what you promised you would do."
"It is only a sign of an agreement that deals with Northern Ireland in the same way as the rest of the United Kingdom."
On Friday, DUP's vice-president Nigel Dodds said he would "rather stay in the EU and stay rather than risk Northern Ireland's position "in the association
Monday, Parliament will provide an indicative vote on Brexit alternatives.
A customs union with the EU is believed to be the most likely preference.