The UK has announced a new set of demands to redraw the post-Brexit trading arrangements it approved with the EU for Northern Ireland.
The government said border checks on goods from Great Britain it signed up to in the 2019 Brexit divorce deal had proved unsustainable.
Brexit Minister Lord Frost said they risked harming business, and were damaging the “fabric” of the UK.
The EU said it would not approve to renegotiate the terms of the 2019 deal.
The checks are included in the Northern Ireland Protocol, a section of the Brexit agreement designed to avoid checks on the island of Ireland’s internal border.
Lord Frost called on the EU to look on the UK’s proposals with “fresh eyes,” adding: “We cannot go on as we are.”
However, he revealed the UK would not be triggering Article 16 of the protocol – which would allow it to postpone parts of the Brexit deal – before talks with Brussels.
He added that the government believed using it was justifiable, but said: “Nevertheless, we have concluded that it is not the right moment to do so.”
Lord Frost told the House of Lords there was a “growing sense in Northern Ireland we have not found the right balance, seen in an ongoing febrile political climate, protests and regrettable instances of occasional disorder”.
He also called on the EU to agree a “standstill period” to prevent a ban on sending chilled meat products such as sausages from Great Britain coming into force in September, when the full terms of the deal kick in.
He later told reporters it was “perfectly normal to change treaties in the light of experience, and it happens all the time”.
In a 28-page document, the UK government suggested changes to:
The biggest practical difficulty, in trade terms, concerns the movement of food from Britain to Northern Ireland, which could then be transported into the EU via the Irish land border.
The prime minister’s former chief adviser, Dominic Cummings, has told BBC political editor Laura Kuenssberg that the protocol had been a “fudge”.
Both sides had wanted to “sign up to something that was not what either side really wanted and which punted difficult questions into the future to figure out later”, he added.