The UK government has published plans to get rid of parts of the post-Brexit deal it signed with the EU in 2020.
It wants to change the Northern Ireland Protocol to make it easier for some goods to flow from Great Britain to Northern Ireland.
But the EU opposes the move, saying that going back on the deal breaches international law.
The UK government disputes this, arguing that the changes will mean the United Kingdom stays together.
The alterations are set out in the Northern Ireland Protocol Bill, to be debated and voted on by Parliament.
The government is promising to remove “unnecessary” paperwork on goods checks and that businesses in Northern Ireland will get the same tax breaks as those elsewhere in the UK.
The bill will also ensure that any trade disputes are resolved by “independent arbitration” and not by the European Court of Justice, it adds.
Foreign Secretary Liz Truss said it was “a reasonable, practical solution to the problems facing Northern Ireland” and that the UK could “only make progress through negotiations if the EU are willing to change the protocol itself”, adding: “At the moment they aren’t.”
“We are very clear that we’re acting in line with the law,” she said.
The government said it would prefer a “negotiated solution” with the EU that avoids the need for the bill to become law.