A UK position paper shared with Brussels this week contradicts some key EU negotiating principles © Reuters

Britain is on a collision course with the EU over fundamental elements of the Brexit transition, as London seeks to potentially extend the period while giving itself the power to reject new EU laws.

A UK position paper, shared with Brussels this week, contains no end date for the transition although British officials maintain it is their intention to set one.

The paper contradicts some key EU negotiating principles and raises the risk of failing to reach a transition deal before a March summit of EU leaders.

The most problematic UK request relates to vetting EU laws it is obliged to follow during the transition, even though it has lost its voice in the EU policymaking process.

Although the UK insists this “implementation period” would probably last about two years, its position paper calls for a potentially longer period to allow for preparations to be made for a future UK-EU trade relationship.

“The UK believes the [transition] period’s duration should be determined simply by how long it will take to prepare and implement the new processes and new systems that will underpin the future partnership,” the document states.

“The UK agrees this points to a period of around two years, but wishes to discuss with the EU the assessment that supports its proposed end date.”

The EU had proposed that the transition end on December 31 2020 and included no renewal clause. British officials have urged the EU side to allow for that date to be extended if necessary.

Downing Street insisted the paper did not represent a change to Theresa May’s position and that the prime minister still wanted a “strictly time limited period of around two years”.

Mrs May’s spokesman argued that the paper was merely intended to provide some flexibility between the European Commission’s proposed end date of December 2020 and Britain’s proposal that the transition should conclude around March 2021.

Steve Baker, a UK Brexit minister, told the BBC that any row over the end date of transition was a “red herring” and that there would be a “fixed date”.

“You can see that they [the EU] want us to exit at the end of the budget period, the prime minister is suggesting two years. But what will be the case is, when we’ve agreed, there will be a fixed date.”

Jacob Rees-Mogg, a Eurosceptic MP, said he had been “assured” by a cabinet minister that “it is not an agreed document merely ‘a draft of a draft’.” The document has been published on the UK government website.

Allies of the UK prime minister rejected suggestions that Britain might try to extend the transition, pointing out that it would be impossible to persuade Tory MPs to accept a deal that prolonged de facto EU membership beyond June 2022, the last possible date for a general election.

Downing Street said the final withdrawal treaty would stipulate a firm end date for the transition period.

Many EU member states expect a mechanism to allow for a one-off, time-limited extension to be included in a final agreement.

Senior EU negotiators have warned the UK that its suggested revisions create “fundamental” problems that may hold up a transition deal, particularly in areas where the UK wants a voice in the shaping and implementation of new EU laws.

“We cannot give them a veto right that EU member states do not have,” said a senior EU official who has seen the UK paper.

The UK proposes a “good faith” clause in the transition deal, to protect it against future decisions intended to undermine UK interests, and a “joint committee” that would decide whether “new acts are necessary”.

According to senior diplomats, the EU side views the requests as politically and legally unacceptable and expects London to “back down” if Mrs May is to secure a transition deal by March.

In its original proposal, the EU side suggested that the UK may, where strictly necessary, be invited to attend meetings or be consulted on decisions. The UK proposal goes further by giving London more clout and making the consultation more automatic in certain areas.

Britain, for instance, has demanded additional rights to influence fisheries policy during the transition, saying catch limits “shall be agreed” with the UK before any EU-wide decision.

The paper also demands that Britain “shall” be consulted on sanctions proposals made by the commission “in good time” and that the UK’s rights to benefit from EU external trade agreements are recognised. Other revisions suggest that some UK regulators can remain a “lead authority” under EU law, and that UK officers could continue to command EU military missions.

Some textual changes appear to have more political than legal implications. The UK side requests that references to the European Court of Justice are removed from the transition agreement, so that it is simply referred to as an institution of the EU.

The duty of “sincere co-operation”, a treaty provision that is a bugbear for some Brexiters who want more independence in trade policy after Brexit, is also deleted from the British version of the text. The UK side argues it is in effect replaced by a separate clause making clear that law is binding during the transition unless otherwise stated.

Additional reporting by Laura Hughes

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