DUP stalwart and MP for East Antrim Sammy Wilson has branded the UK government as "spineless, weak-kneed and Brexit-betraying" after it published the details of the deal it reached with the DUP on post-Brexit trade arrangements.
It comes as the UK government unveiled details of the deal and hailed it as the "right" one to restore power-sharing at Stormont.
"When the Northern Ireland Assembly sits, ministers and Assembly members will be expected by law to adhere to and implement laws which are made in Brussels, which they had no say over and no ability to amend, and no ability to stop," Mr Wilson said.
"This is a result of this spineless, weak-kneed, Brexit-betraying government, refusing to take on the EU and its interference in Northern Ireland."
He added: "Is Northern Ireland going to find it's got the ability to stay tied to the United Kingdom, or will the government proceed happily to change laws here regardless of the impact it has on Northern Ireland?"
Northern Ireland Secretary Chris Heaton-Harris said EU law alignment would no longer automatically apply under the government's plans, adding legislation will be passed to reaffirm Northern Ireland's constitutional status.
In response to Mr Wilson, he said: "On the fourth anniversary of leaving the European Union, I can tell him absolutely that this agreed package of measures will not change the freedoms and powers we have secured through Brexit or through the Windsor Framework.
"It will not reduce our ability to diverge nor our commitment to do so should it be in the interest of the United Kingdom," he said.
Mr Heaton-Harris also praised DUP leader Jeffrey Donaldson for his commitment to the union and work during the negotiations. He told MPs it was time to build on the progress of the last 25 years.
"The result, as I hope honourable members will agree, is a deal that, taken as a whole, is the right one for Northern Ireland and for the union," he said.
"With this package it is now time for elected representatives in Northern Ireland to come together, to end the two years of impasse and start work again in the interests of the people that elected them," Mr Heaton-Harris added.
"Today we have presented a plan which will deliver the long-term change that Northern Ireland needs. It will strengthen Northern Ireland's place in our union and guarantee the free flow of goods across the entire United Kingdom.
"It's only by sticking to this plan that we will become a more united and prosperous country together," he said.
Tánaiste 'does not anticipate any difficulties on the EU side'
The Tánaiste and Minister for Foreign Affairs Micheál Martin has that now is a moment "to grasp for the benefit of all people living in Northern Ireland and indeed on the island of Ireland".
Speaking in Belfast today, Mr Martin said he warmly welcomed the decision of the DUP to agree to return to power-sharing in Northern Ireland.
He held a series of meetings with political leaders today, as the British government published details of its deal with the DUP on post Brexit trading arrangements.
The Tánaiste said he doesn't anticipate any particular difficulties on the EU side in relation to the new deal.
He said he cannot pre-empt what the EU-UK Joint Committee will do but added that the EU wants a close relationship with the UK.
"We align on many, many issues, and the leadership of the European Union, the British prime minister, British government and indeed the Irish Government want sensible, warm relationships, and it's in that spirit than that these issues will be approached," Mr Martin said.
In relation to the EU single market, Mr Martin said that when it came to goods entering Northern Ireland from Great Britain and staying in Northern Ireland.
He said: "We've always been of the view the more streamlined and seamless one can make that, the better all round, because we want any of the frameworks we've put in place to work for industry, for business, and for jobs in Northern Ireland."
Mr Martin said that the Windsor Framework was a "significant advance" on the Northern Ireland Protocol from a unionist perspective, and that advocacy from unionism has "paid dividends in respect of the Windsor Framework".
He said he sensed from talking to the political parties that there is a "recognition and a realisation that this is a moment in time now when the restoration of the Assembly must lead to a sustainable restoration, must lead to focus on the issues that matter to the people of Northern Ireland".
The Tánaiste said that this was a "very big moment" for Sinn Féin's Michelle O'Neill who is on the cusp of becoming First Minister.
US Democratic Congressman Richard Neal hailed the agreement that could see the return of devolved government as a victory for the people of Northern Ireland.
"After nearly two years of delay, Stormont is one step closer to resuming the people's business. This is a victory for democracy and for the people of Northern Ireland," he said.
"When the United States helped broker the Good Friday Agreement, cementing its place as a guarantor of the agreement, it did so with one primary objective: ensuring every community had a voice in the pursuit of peace and prosperity.
"With the restoration of power-sharing on the horizon, the people are the winners. Their voices will be heard once again," Mr Neal added.
Time to 'scrutinise' the deal
Conservative former minister Theresa Villiers and Conservative MP William Cash also questioned the influence of EU laws on Northern Ireland.
Ms Villiers said: "I'm sure there will be much to welcome in the papers published today and we'll need to scrutinise them carefully in the 30 or so hours before we're going to be asked to vote on them."
Mr Cash asked what was being done to ensure the UK government can "remove or veto the imposition of EU laws on Northern Ireland".
Mr Heaton-Harris said the Assembly will have a powerful "democratic safeguard" when it comes to EU laws.
SDLP leader Colum Eastwood described it as a "very good day for the people of Northern Ireland" before suggesting the UK and Irish governments, along with the political parties, should look at how to reform the Good Friday Agreement institutions to "make sure no one party can ever pull them down again".
Some MPs expressed concerns over the amount of time expected to be available in the House of Commons on Thursday to debate statutory instruments (SIs) to enshrine several of the deal's commitments in law.
DUP MP for South Antrim, Paul Girvan said: "We very much feel we're being bounced on a timetable where we're not going to get through the detail that is supposedly in the SIs and also this document."
Additional reporting: Laura Hogan
