Liz Truss risked a trade war with the EU and accusations of lawbreaking as she published legislation that would allow exports from Britain to Northern Ireland to follow UK or EU standards and checks.
Truss published the Northern Ireland protocol bill, which said the legislation would fix issues with the post-Brexit protocol by easing checks for firms selling goods from Britain destined for Northern Ireland rather than the EU. It would also scrap the European Court of Justice as the arbiter of trade disputes and move to an independent mechanism.
The move is illegal under international law as it gives ministers the power to disapply parts of the protocol without the agreement of Brussels, according to the EU, legal experts and even some Conservative MPs.
One of the biggest changes is the introduction of a choice for British firms importing to Northern Ireland between meeting EU or UK standards on regulation, which are expected to become more and more divergent. It would allow for fewer customs checks for goods destined for Northern Ireland and a red lane with existing checks for goods destined for EU countries.
Two other measures included bringing Northern Ireland's tax break and spending policies into line with the rest of the UK and changing oversight of trade disputes so that they are resolved by independent arbitration rather than the European court of justice.
The legislation will encounter serious opposition in the House of Commons and Lords, with doubts as to whether Boris Johnson will be able to pass it. The bill has some critics on the Eurosceptic right, including Northern Ireland's DUP, as well as some on the one nation centrist wing of the Tories.
The DUP blocked the progress towards power-sharing in Northern Ireland before parliament breaks up for summer recess but government sources said it would be good to see a vote on the bill before it breaks up for summer recess.
A majority of the members of the Northern Ireland assembly from Sinn F in, the SDLP, wrote to Johnson on Monday that they could not support the move and warned that it would be in the face of the expressed wishes of not just most businesses, but most people in Northern Ireland. The assembly is due to vote on whether it will give consent for the operation of the protocol in 2024, four years after it came into force.
With opposition mounting, there are some doubts that the legislation will get anywhere. The government is insisting that it would still find a solution to fix problems with the protocol. Ireland said on Monday that Truss had not engaged in negotiations with the protocol since February.
A phone call between Truss and Simon Coveney, Dublin's foreign affairs minister, last just 12 minutes on Monday morning. A spokesman for Ireland's Department of Foreign Affairs said: "Coveney said that publishing legislation that would breach the UK's commitments under international law, the Brexit withdrawal agreement and Northern Ireland protocol is deeply damaging to relationships on these islands and between the UK and EU. David Lammy, the shadow foreign secretary, said it was a desperate attempt by Boris Johnson to distract himself from the drama of his leadership crisis and called for the government to publish its legal advice in full.
Britain should be a country that keeps its word. By tearing up the protocol it negotiated a couple of years ago, the government will damage Britain's reputation and make finding a lasting solution more difficult.