MOST of Stormont’s politicians have rejected Boris Johnson’s “reckless” plan to override the Northern Ireland Protocol “in the strongest possible terms”.

In a signed joint letter, 52 of the 90 members of the legislative assembly (MLAs) also accused the Prime Minister of "fabrication" and said he and his government were seen to lack “trust and honesty”.

The MLAs, who represent Sinn Fein, the SDLP and the cross-community Alliance Party, blamed Mr Johnson for demanding the hard Brexit that created the current Protocol.

Mr Johnson today claimed legislation due to be introduced at Westminster today to disapply parts of the protocol ws “no big deal”, despite the threat of a trade war with the EU.

The Prime Minister said the proposed changes were a “relatively trivial set of adjustments in the grand scheme of things”, but critics said they could breach international law.

In the letter, the MLAs remind Mr Johnson their parties collectively received a majority of the votes cast in last month's NI Assembly elections.

They wrote: “We reject in the strongest possible terms your Government's reckless new Protocol legislation, which flies in the face of the expressed wishes of not just most businesses, but most people in Northern Ireland. 

“The Protocol is itself a product of the hard Brexit you personally championed and a withdrawal deal you personally signed. 

“Whilst not ideal, the protocol currently represents the only available protections for Northern Ireland from the worst impacts of that hard Brexit. 

“The Protocol also offers clear economic advantages to our region, and the opportunity for unique access to two major markets

“The fact that you have removed this advantage from businesses in Great Britain, at a clear economic cost, does not justify doing the same to businesses in Northern Ireland.”

The group said they wanted to see the arrangements “work as smoothly as possible”, but stressed the way to achieve that was engagement with the European Union. 

“But this must be on the basis of trust and the rule of law rather than law breaking and unilateral abrogation of treaty obligations,” they went on. 

“It is also deeply frustrating that you and your ministers continue to misrepresent our desire to see smooth implementation as an endorsement of your Government's reckless actions on the Protocol - it is categorically not. 

“Finally, we strongly reject your continued claim to be protecting the Good Friday Agreement as your Government works to destabilise our region. 

“To complain the Protocol lacks cross-community consent, while ignoring the fact that Brexit itself - let alone hard Brexit - lacks even basic majority consent here, is a grotesque act of political distortion.

"Your claims to be acting to protect our institutions is as much a fabrication as the Brexit campaign claims you made in 2016. 

“The way to build trust and consent in our arrangements is to engage seriously with the EU on making them work, and to be honest with all parties about the inevitable consequences of leaving the Single Market and Customs Union. 

“Sadly, trust and honesty are not words readily associated with you or your Government.

“We will resolutely oppose this reckless Bill and continue to promote post-Brexit solutions on the basis of trust and honesty.” 

The protocol is seen by Northern Ireland Unionists as a threat to the UK, as it aligns the province with EU rules, with a trade border in the North Sea between NI and Great Britain.

The DUP has refused to enter a powersharing executive with Sinn Fein unless the protocol is substantially rewritten or scrapped.

The new Westminster legislation will give ministers powers to override elements of the protocol, which was jointly agreed by Mr Johnson’s Government and the EU 

It currently requires regulatory checks and customs declarations on goods moving between Great Britain and Northern Ireland, because they could flow through the open border with Ireland into the EU’s single market.

The new Northern Ireland Protocol Bill will see the Government reduce the checks on the movement of goods across the Irish Sea, with a possible “green lane” to fast-track goods staying in Northern Ireland, and another for those moving onwards into Ireland and the EU. 

It could also see businesses in Northern Ireland given the ability to choose whether to follow UK or EU regulations, depending on who they are trading with.

The Irish premier Micheal Martin said it was regrettable that the UK appeared set to renege on an international treaty.

Speaking in Cork today, he rejected the assertions from the British Government that the EU has been inflexible during negotiations.

He said: “It’s very regrettable for a country like the UK to renege on an international treaty.

“I think it represents a new low point because the natural expectation of democratic countries like ourselves, the UK and all across Europe is that we honour international agreements that we enter into.” This agreement was ratified by the British parliament, it was approved by the British prime minister.

“I’ve had this discussion with him and, in our view, the only way to resolve issues around the operation of the protocol is to have substantive negotiations between the UK and the EU.

“We do not accept the presentation by the British Government and certain ministers to the effect that the EU is inflexible. That is most definitely not the case and the EU has been very proactive in the last year in endeavouring to seek solutions to issues around the operation of the protocol.”

He called on the British Government to enter into negotiations and discussions to resolve the issues.