The EU quickly threatened legal action in response to the new legislation, while Dublin called it "a particular low point in the UK's approach to Brexit".

London claims the bill will address
London claims the bill will address "burdensome customs processes, inflexible regulation, tax and spend discrepancies and democratic governance issues". (Reuters)

The UK government has introduced legislation to rip up post-Brexit trading rules for Northern Ireland, despite the possibility that could spark a trade war with the European Union.

Monday's bill proposes overriding the EU withdrawal treaty that the UK signed, although the government in London insists it is not breaking international law.

Foreign Secretary Liz Truss spoke to European Commission Vice President Maros Sefcovic and Ireland counterpart Simon Coveney to inform them of the bill, calling it a "reasonable, practical solution to the problems facing Northern Ireland".

But Sefcovic said that the EU would not renegotiate its divorce deal and that Brussels would now consider reopening a suspended "infringement procedure" against Britain, as well as opening fresh cases.

"It is with significant concern that we take note of today's decision by the UK Government to table legislation," he said in a prepared statement to reporters in Brussels.

Coveney told Truss the move marked "a particular low point in the UK's approach to Brexit" and was "deeply damaging to relationships on these islands and between the UK and EU".

READ MORE: UK unveils overhaul of EU trade deal in Northern Ireland

Green and red channels

London claims the bill will address "burdensome customs processes, inflexible regulation, tax and spend discrepancies and democratic governance issues" that are "undermining" peace in Northern Ireland.

Irish Foreign Secretary Coveney, however, says "the UK's unilateral approach is not in the best interest of Northern Ireland and does not have the consent or support of the majority of people or business in Northern Ireland."

The protocol requires checks on goods arriving from England, Scotland and Wales, to prevent them from entering the EU's single market via the Republic of Ireland and to avoid a return to a "hard border".

The UK bill proposes scrapping most of the checks, creating a "green channel" for British traders to send goods to Northern Ireland without making any customs declaration to the EU.

The EU would have access to more real-time UK data on the flow of goods, and only businesses intending to trade into the single market via Ireland would be required to make declarations via a "red channel".

The EU would need to trust the UK to monitor the flow, London said, promising "robust penalties" for any companies seeking to abuse the new system.

Prime Minister Boris Johnson insisted that the move was "the right way forward" and was needed to maintain the "balance and the symmetry" of the Good Friday peace agreement between pro-UK unionists and nationalists who want a united Ireland.

Since recently surviving a confidence vote in his leadership, Johnson has reportedly been under pressure from pro-Brexit Tory hardliners to toughen the bill and remove oversight of the protocol by the European Court of Justice.

READ MORE: UK urges Northern Ireland parties to form government under Brexit shadow

Source: TRTWorld and agencies