Plan has enraged EU and many Tories but sources say No 10 thinks it will move talks along
David Frost, Britain’s chief negotiator, arrives in Downing StreetDavid Frost, Britain’s chief negotiator, arrives in Downing Street on Friday. Photograph: Aaron Chown/PA

Britain’s Brexit negotiators believe Downing Street’s plan to break international law, pushing the trade and security negotiations to the brink, may have helped reboot the talks by offering Brussels a reality check about the looming danger of a no-deal outcome.

The publication of the internal market bill on Wednesday, under which key parts of the withdrawal agreement agreed last year would be negated, has enraged the EU and prompted an internal rebellion within the Conservative party.

Brussels has set Boris Johnson a three-week deadline to ditch his plans or face financial and trade sanctions, with the clear suggestion that negotiations over a future relationship will fail unless the most contentious parts of the proposed legislation are removed.

In a sign of the EU’s anger at Johnson’s move, a committee of MEPs coordinating the European parliament’s stance on Brexit, issued a statement on Friday stating they would refuse to ratify any trade and security deal if the UK government had breached the withdrawal agreement or threatened to do so.

A Tory rebellion against Johnson’s bill is gathering pace: an amendment to the internal market bill by the former minister Bob Neill would give parliament a veto on overriding the UK-EU divorce deal.

Late on Friday afternoon, the prime minister sought to quell discontent among some Conservative colleagues over the bill by addressing MPs on the issue during a Zoom call although no questions were taken.

In the call, which was disrupted at one stage when the videolink went down, Johnson reportedly stressed that the clauses in the bill were necessary to prevent a foreign power from “breaking up our country”, as well as insisting there were still hopes of a Canada-style trade deal. In a piece in saturday’s Telegraph he claimed the EU was threatening to “blockade” Northern Ireland. “Let’s make the EU take their threats off the table,” he wrote.

However, Neill was unconvinced. “I believe [changing the withdrawal agreement] is potentially a harmful act for this country, it would damage our reputation and I think it will make it harder to strike trade deals going forward,” he told Channel 4 News after the call.

Earlier there had been excoriating criticism of the internal market bill by the former Tory leader and Brexit supporter Michael Howard, who predicted many of his colleagues would oppose it and said he would be surprised if it got through the House of Lords, where the government lacks a majority.

But Downing Street believes the row with the EU may ultimately prove to be a welcome disruption to the talks, which had been in deadlock throughout the summer over the most thorny issues of the government’s future domestic subsidy regime and access to British waters for EU fishing fleets.

The British negotiating team, led by David Frost, believes EU capitals are freshly focused on the trade and security negotiations, with Brussels clear-sighted on the risk of the talks collapsing.

Negotiations between the teams led by Frost and the EU’s chief negotiator, Michel Barnier, are to continue next week with both sides in agreement that a deal must be ready to be endorsed by EU leaders by 15 October.

“Talks this week have been relatively more constructive than you might expect, but ultimately progress will be determined by whether we get more realism from them on the key areas of divergence,” said one senior UK negotiating official.

Progress was claimed to have been achieved after the EU was said to have dropped its policy of “parallelism”, or the insistence that they had to make progress on all elements of talks, ranging from fundamental stumbling blocks of state aid and fisheries to the easier issues.

Downing Street’s view of a fresh impetus to the negotiation was not echoed by Barnier in a statement issued at the end of the eighth week of negotiations. He said Brussels had offered to accommodate British red-lines in the negotiation, including a major windfall for British fishing boats and the acceptance that the UK would not follow EU law, but Frost had “not engaged in a reciprocal way on fundamental EU principles and interests”.

One senior EU source said the week’s talks had been “better than you might expect” but that Brussels was simply focused on carrying on the negotiations until it was clear there was no chance of a deal. “We don’t want to get caught out – there isn’t time to waste so this is two sets of civil servants doing their jobs,” said a senior EU diplomat.

British sources close to the negotiations said they did not recognise Barnier’s account of the latest talks. “We’ve been engaged in talks pretty consistently for many months now,” one UK source said. “The problem is the EU seems to define engagement as accepting large elements of their position. Rather than being engaged in discussions and that’s one of the problems that we’ll need to overcome.”

The government on Wednesday published a thin document on its plans for subsidy control in which it pledged not to return to the bailouts for failing companies that were seen in the 1970s. The UK said it would consult over how to control subsidies in the “coming months”.

Barnier said the proposal did not offer the assurance the EU needed and fell “significantly short of the commitments made in the political declaration”, in reference to the paper agreed by Johnson and EU leaders last year about the outline of a deal.

A UK source said: “We believe statements that we put out on Wednesday constitute a very clear statement of the direction, about domestic policy and how [it] interacts with these negotiations while still giving room to have a constructive discussion on the subject. And we’re sorry that it wasn’t taken in that spirit.”

Howard said it was “a very sad day last week” when the Northern Ireland secretary, Brandon Lewis, admitted that amending the UK’s Brexit deal would break international law.

“I never thought it was a thing I’d hear a British minister, far less a Conservative minister, say, which is that the government was going to invite parliament to act in breach of international law,” Howard told Sky News. “We have a reputation for probity, for upholding the rule of law, and it’s a reputation that is very precious and ought to be safeguarded, and I am afraid it was severely damaged by what was said on Tuesday and by the bill which is currently before parliament.”

Momentum gathered pace on Friday as Neill’s initiative, which is being backed by the former ministers Damian Green Oliver Heald, was also signed by Simon Hoare, the chair of the Northern Ireland affairs select committee.

Hoare tweeted that US figures “had a point” in warning that potential destabilisation of the Good Friday agreement could result both in a no-deal Brexit and no trade deal with the US.