The draft Brexit withdrawal deal presents a "false choice" as a legal backstop is not needed to maintain a free flowing Irish border, DUP leader Arlene Foster has said.
Ms Foster pointed to remarks by Taoiseach Leo Varadkar that he was "not contemplating" a hard border in the event of a no-deal Brexit as evidence the issue was "only ever a negotiating tactic by the European Union".
Ms Foster said: "The Taoiseach's comments that the Irish Government is not contemplating a hard border in the event the Withdrawal Agreement is rejected by Parliament underlines why a focus on the backstop was only ever a negotiating tactic by the European Union.
"We have been told that the backstop is only necessary to prevent such a hard border, but these comments make it clear that the EU's insistence on a backstop was not aimed at this."
Ms Foster said that the EU’s focus on the border issue has only ever been "a negotiating tactic to secure its own aims in the negotiations".
The DUP leader added: "The comments also further underscore how the inclusion of a border down the Irish Sea within the current Withdrawal Agreement is not only unacceptable, but is also unnecessary.
"The Withdrawal Agreement was based on the false choice that an internal UK border was the only way to prevent a hard border between Northern Ireland and the Republic."
While Mr Varadkar said on Sunday that he was not contemplating a hard border, on Friday he said one would be "very difficult to avoid" in a no-deal scenario.
Ms Foster added: "The agreement that has been put on the table is clearly not a good deal and no one should be forced into accepting another false choice.
"This really bad deal would lock us into the EU with no way out. We would be trapped. Those attempting to sell the current deal are using the threat of no-deal as the only other option.
"I appreciate the concerns people have about a no deal but this should not be a binary choice. It is absolutely clear that it is time to work for a better deal."
It comes as British Prime Minister Theresa May said her Brexit plan was the best for jobs across the country, as she battles to keep her own post in Downing Street.
In a message to her political rivals, Mrs May stressed that Brexit was not an exercise in "political theory" but affected people's lives and livelihoods.
Mrs May said the withdrawal agreement had been "agreed in full" by both sides.
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Mrs May said she would travel to Brussels this week to meet European Commission President Jean-Claude Juncker.
Tánaiste and Minister for Foreign Affairs Simon Coveney and Minister of State for European Affairs Helen McEntee are also in Brussels to discuss the draft withdrawal agreement ahead of next weekend's summit.
Mr Coveney said Mrs May should not be underestimated in her ability to get the Withdrawal Agreement passed in the House of Commons.
In an interview with RTÉ News, Mr Coveney said: "People have underestimated Theresa May over and over again. I think they're wrong to. I think she is a very steely, determined person. I think she has got a good deal for Britain - for the United Kingdom as a whole, I should say - and she has followed through on her commitments to Ireland and the EU."
He added: "We should not accept that premise that it's not going to be passed in Westminster. I think we all have a job to do to explain it and reassure people of what's in this text.
"If you listen to what business are saying in Northern Ireland, in most parts of the United Kingdom, obviously in Ireland as well, people are saying this is a deal we should accept.
"The absence of agreement on this deal means a lot of uncertainty, a lot of chaos quite frankly, and the potential for the Brexit project…to unravel altogether."
Mr Coveney said Mrs May was offering people a stark choice between a compromise deal that allowed for a "managed, sensible Brexit" that protected both EU and British interests, and a "chaotic" no deal.
Meanwhile, Northern Ireland Secretary of State Karen Bradley has said WTO rules are clear that checks would be required between Ireland and Northern Ireland if Britain crashed out of the EU without a deal.
"The fact is that the WTO is very clear that if there are two different customs territories, checks have to be able to be carried out on a contemporaneous basis on consignments passing between the two territories," she told reporters.
"How this is done would be something we could negotiate. We will do, as the UK government, everything we can do to avoid there being a hard border on the island of Ireland. We do not want to see physical infrastructure but WTO rules are clear."
Ms Bradley is continuing her efforts to garner support for the Brexit deal.
At a meeting of business groups in Belfast, Ms Bradley said that the choice now is to accept what is a workable deal or go back to square one on Brexit.
Ms Bradley told the meeting the agreement is good for the people and businesses of Northern Ireland; it prevents a hard border, upholds the Good Friday Agreement, and maintains the constitutional and economic integrity of the UK.
Elsewhere, several hundred sixth form pupils from a number of Belfast grammar schools staged a lunchtime walk out today, as part of a campaign aimed at getting a people's vote on the final Brexit deal.
The walk outs at Lagan College, Methodist College, Wellington College and St Patrick's Knock were organised by the Our Future Our Choice campaign group.
Additional reporting: Fiona Mitchell, Reuters, Tommie Gorman
