The boss of the UK Government's legal department has quit his post over Boris Johnson's plans to tear up parts of the Brexit divorce deal, it was claimed today.
Sir Jonathan Jones is said to have resigned because of disagreements over Number 10's decision to try to override parts of the accord struck with the EU last year which relate to the Northern Ireland border protocol.
The Financial Times reported that the permanent secretary was 'very unhappy' about the stance taken by Mr Johnson. He becomes the sixth senior civil servant to quit Whitehall this year amid an ongoing war between the civil service and Number 10.
Sir Jonathan's apparent decision to quit came after ministers tried to downplay the significance of Mr Johnson's plans, insisting it amounted to tying up 'loose ends'.
Meanwhile, US politicians warned this morning there would be no trade deal done between Washington and London if the Government's actions on Brexit undermine the Good Friday Agreement.
Brendan Boyle, a Democratic member of the US House of Representatives, said: 'I thought, like most of us on this side of the Atlantic, that the issue was resolved last December when the British signed up to the international treaty setting out the Withdrawal Agreement, making sure that the Good Friday Agreement would not be violated and that there wasn't a danger of a return of a hard border on the island of Ireland.
'So the fact that now, less than a year later we are back at this point, is a genuinely shocking development.'
He added: 'If the UK in leaving the European Union, which is fully their right to do, if the UK does it in such a way that it violates the Good Friday Agreement there will be no US UK free trade agreement. Period.
'So the UK needs to understand there will be consequences that stretch well beyond trust dealings with the EU on this matter.
Brexit trade talks between the UK and EU are on the brink of collapse after Mr Johnson warned that the 'contradictory' terms of Britain's split from Brussels must be overhauled.
Michel Barnier is arriving in London today for a make-or-break round of negotiations amid mounting gloom about the prospects of a breakthrough.
The standoff turned nasty yesterday as Brussels voiced fury at UK threats to override parts of the Withdrawal Agreement thrashed out last year. Legislation would unilaterally 'clarify' key parts of the settlement, including customs rules for Northern Ireland, that the EU insists should be resolved by a joint committee.
Despite Mr Barnier warning that step would end hopes for a trade deal, the PM's chief negotiator Lord Frost increased the temperature again today, demanding 'more realism' from the EU that the UK was now a sovereign country.
Michel Barnier (right) is arriving in London for a make-or-break round of trade negotiations with the UK's David Frost (left in Downing Street) amid mounting gloom about the prospects of a breakthrough
Boris Johnson sent an ultimatum to the EU that he will 'not back down' yesterday, in another effort to convince the bloc he is not bluffing about reverting to basic trade arrangements
In a message kicking off the latest round of discussions, the peer said the two sides 'can no longer afford to go over well-trodden ground' and progress on the key stumbling points - fishing rights and the UK obeying EU rules - was essential this week if a deal was to be done in time for the end of the transition period in January.
Medical leaders have also cautioned that a combination of a chaotic change in trade arrangements and resurgent coronavirus this winter could 'overwhelm' the health service.
Mr Johnson sent an ultimatum to the EU that he will 'not back down' yesterday, in another effort to convince the bloc he is not bluffing about reverting to basic trading arrangements at the end of the transition period.
The UK formally left the EU on January 31 this year.
However, the two sides moved seamlessly into a status quo transition period lasting until December 31.
This time was set aside to allow Brussels and Britain to hammer out the terms of their future relationship.
Trade talks started in March and the eighth round of formal negotiations is due to get underway in London tomorrow.
However, talks are at a standstill amid disagreements on fishing rights and whether the UK will sign up to Brussels' rules and regulations.
Downing Street has said it does not want talks to drag into the autumn while the EU wants a deal done by the of October in order to give member states enough time to ratify it before the end of the transition period.
Given the time constraints and the lack of progress being made both sides now view a deal by the end of the year as unlikely.
Leaked diplomatic cables showed growing unease among European officials over the UK's hardline stance, with suspicions that Mr Johnson is holding off on a compromise until the last minute to secure the best possible terms.
There is disquiet among some senior Conservatives over 'dangerous' plans to revisit the Withdrawal Agreement.
The UK government is pushing through legislation that could effectively override parts of the divorce deal.
The laws will unilaterally resolve crucial issues in the Northern Ireland protocol - including deciding what goods require customs checks between mainland Britain and the province.
Ministers say that the changes are essential to avoid 'confusion' if there is no settlement by the end of the transition period in December.
However, Brussels insists that under the divorce deal those details can only be finalised by a joint committee made up of members from both sides.
The One Nation group of moderate Tory MPs, which met last night, is said to be alarmed by the strategy, according to the Times.
One of the MPs said: 'This would clearly have some real issues in terms of our status as a country. If we breach an international agreement it will affect our ability to do deals with others. The ramifications of doing this are serious.'
But a No10 source said: 'The protocol is contradictory in some respects - it talks about protecting the EU single market but also giving Northern Ireland unfettered access to the UK market. You can't have both.
'Without a trade deal, all goods passing from the mainland to Northern Ireland would be subject to tariffs, because they would be classed as being 'at risk' of being sold on to the EU market.
'Even though traders could later claim back the money by proving the goods didn't leave the UK, the administrative costs would be considerable.'
Downing Street has sought to increase pressure on the bloc in recent weeks, and it appears to have provoked a reaction, according to messages sent to EU capitals from Brussels, seen by the Guardian.
European Commission president Ursula von der Leyen warned there could be no backtracking by the UK on its previous commitments if it wanted to reach a free trade agreement
EU commission president Ursula von der Leyen delivered a thinly-veiled warning to the