(Bloomberg) -- The U.K. issues another batch of papers on its preparations for a no-deal Brexit. Negotiations with the European Union remain on a knife-edge over how to keep the Irish border open after Britain leaves the bloc.

May Rules Out Permanent Backstop (12:15 p.m.)

Prime Minister Theresa May would never agree to a Brexit deal that left the U.K. permanently tied to the so-called Irish backstop, her spokeswoman Alison Donnelly told reporters.

The premier’s position is that the backstop -- a legal guarantee to ensure the Irish border remains all but invisible after Brexit -- must be temporary until the U.K.’s future relationship with the European Union is set, she said. The government wants that to be by the end of 2021 at the latest.

Earlier:Hammond Promises ‘Deal Dividend’ in Warning to BrexiteersDUP Leader Issues Threat to May as Brexit Compromise Edges NearMay’s Deal in Peril as Brexiteers, DUP Object: Brexit BulletinWhat if Ireland Scuppers Theresa May’s Brexit?: Therese RaphaelA Cautionary Tale for How Next Week’s Brexit Summit Can Collapse

To contact the reporters on this story: Robert Hutton in London at rhutton1@bloomberg.net;Tim Ross in London at tross54@bloomberg.net;Alex Morales in London at amorales2@bloomberg.net

To contact the editors responsible for this story: Flavia Krause-Jackson at fjackson@bloomberg.net, Stuart Biggs

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