Britain must agree to stay under the jurisdiction of the European Court of Human Rights if it wants a trade deal with the EU, Brussels will insist – in a move likely to trigger another row with right-wingers in the Conservative party.

A leaked draft European Parliament motion obtained by The Independent and due to be published in the coming weeks spells out a series of new demands from the body’s Brexit leadership for the next phase of talks – and threatens that it will use its veto if they are not met.

Stipulations include “that the UK continues to guarantee fundamental human rights as laid down in the European Convention on Human Rights” as well as other demands to automatically implement new EU laws created after 2019, and a ban on “opt-outs” from Brexit for Britain’s car-making and financial services industries.

The motion says that the Parliament “will accept a framework for the future EU-UK relationship as part of the withdrawal agreement only if it is in strict concordance” with the list.

Another section of the leaked motion gives an insight into negotiations so far, revealing that the UK has guaranteed the rights of the families of EU citizens living in the UK, including as-yet unborn children, and accepted European Court of Justice jurisdiction over their rights. It also shows that the EU has accepted that British citizens living in the EU at the point of Brexit will be able to move freely between other countries – a point especially important to frontier workers.

Theresa May’s position on the European Court of Human Rights is unclear; last year she said the UK “should leave” the court “regardless of the referendum result”, arguing that it “can bind the hands of Parliament, adds nothing to our prosperity, makes us less secure by preventing the deportation of dangerous foreign nationals”.

The Conservative 2017 manifesto however said the UK would not leave the ECHR “while the process of Brexit is under way” although it did not rule out leaving it after the process is complete.

Following that manifesto commitment and a further terror attack, however, the Prime Minister said in a speech ahead of election day 2017 that if “human rights laws get in the way” of her security policies she would change them – calling into question the earlier pledge.

Whatever the Government decides, however, increasingly influential elements of the Conservative Party are set on leaving the convention. Jacob Rees-Mogg, one of the bookies’ favourites for the next Tory leader, has said ECHR rulings have “no support from the democracy of the United Kingdom” and that “allowing foreign judges to rule on our laws lacks legitimacy”. Former Justice minister Lord Faulks in April urged Ms May to use the opportunity of Brexit to quit the convention.

Though the Parliament is not directly conducting Brexit negotiations, it holds a veto on any final deal, and its Brexit coordinator Guy Verhofstadt has been working closely with the European Commission’s chief negotiator Michel Barnier.

Theresa May is having difficulty bringing the DUP's Arlene Foster on side with her vision of Brexit (PA)

The motion, which is almost certain to be passed by a large majority, was due to be unveiled and voted on during a European Parliament session in Strasbourg next week. The Independent however understands that voting on it could be postponed because of the difficulties the Prime Minister is facing over the issue of the Northern Ireland border.

Theresa May has said she will return to Brussels this week for more talks after further consultation with the DUP, who blocked a deal when she travelled to the EU capital on Monday for a working lunch with Jean-Claude Juncker. No date or time for her arrival has yet been set, however.

Brexit: the deciders Show all 8 1 /8 Brexit: the deciders Brexit: the deciders European Union's chief Brexit negotiator, Michel Barnier Getty Brexit: the deciders French President Emmanuel Macron Getty Brexit: the deciders German Chancellor Angela Merkel Reuters Brexit: the deciders Commission President Jean-Claude Juncker EPA Brexit: the deciders The European Parliament's chief Brexit negotiator Guy Verhofstadt Getty Brexit: the deciders Britain's Prime Minister Theresa May Getty Images Brexit: the deciders Britain's Chancellor of the Exchequer, Philip Hammond PA Brexit: the deciders After the first and second appointed Brexit secretaries resigned (David Davis and Dominic Raab respectively), Stephen Barclay is currently heading up the position PA

The European Court of Human Rights, whose seat is in Strasbourg, enforces the convention upon its signatories.