A UK Bill on the Northern Ireland Protocol will potentially remove any checks on goods entering the province from Great Britain and is expected to be tabled this week.
According to RTE News, the legislation will allow ministers to override the protocol unilaterally and focus on a so-called "dual regulatory regime", with goods staying between Northern Ireland and Britain not requiring checks.
The legislation was initially expected to be published on Wednesday, however it is understood the introduction of the first stages of the Bill was held up over DUP objections to some aspects of the plans.
Instead, it is likely to come to the House of Commons on Thursday.
DUP leader Sir Jeffrey Donaldson said he met a number of politicians in Westminster, including Labour leader Sir Keir Starmer, and urged parliamentarians to “recognise the seriousness of this matter and resist the temptation to play politics with Northern Ireland”.
Mr Donaldson is also set to give evidence to the House of Lords Northern Ireland Protocol sub-Committee on Wednesday.
According to reports, the Bill is expected to remove the Irish Sea border that has proved extremely contentious to unionists across Northern Ireland, instead replacing it with a robust surveillance regime.
The move at Westminster will also give future ministers enabling powers to enact secondary legislation that could be introduced depending on the outcome of negotiations with the European Union.
Foreign Secretary Liz Truss has previously outlined that the UK intends to legislate to override parts of the deal.
Opposition to that deal has seen the DUP block efforts to restore powersharing in the region.
Speaking during a visit to Strasbourg on Tuesday, Taoiseach Micheal Martin urged the UK Government not to act unilaterally over the protocol.
He said: "Europe will respond in a calm and a firm way to whatever decisions are taken by the British Government and in relation to whatever legislation is published and enacted.
"I am very clear that unilateralism will not work.
"I would say to the United Kingdom Government it needs to think of the people of Northern Ireland and not to do anything which undermines the economic wellbeing of the people of Northern Ireland."
The reports come amid intense divisions within the Conservative Party following a vote of no confidence in Prime Minister Boris Johnson on Monday.
Tory MPs voted by 211 to 148 in support of the Prime Minister
Irish Foreign Minister Simon Coveney warned that the divisions in Mr Johnson’s party must not dictate the UK approach to negotiations over the protocol.
He claimed the British Government had not shown the necessary "seriousness" to reach an agreement on the post-Brexit arrangements for Northern Ireland.
He said the UK Government was instead "threatening to publish legislation this week which would effectively be using British domestic law to breach international law by setting aside elements of their treaty obligations".
"That would be a big mistake I think politically, because I think it'll cause an awful lot more problems than it solves.
"I certainly hope that's not the price of the British Prime Minister maintaining majority support within his own party."