ARLENE Foster, the Democratic Unionist leader, has warned that it would be "catastrophic" to create a barrier between Great Britain and Northern Ireland as she travelled to Brussels for key talks today.

Mrs Foster is to meet Michel Barnier, the European Union's chief Brexit negotiator, to set out her "blood red" line on the issue, warning against any attempt to "annex" Northern Ireland.

The UK Government has promised to set out further proposals on the "backstop" arrangement aimed at avoiding a hard border with Ireland with speculation that it could involve regulatory checks on goods travelling between the British mainland and Northern Ireland.

The DUP's 10 MPs play a critical role in propping up Theresa May's minority administration at Westminster and Mrs Foster said her party's only red line was the prevention of a new border being created in the Irish Sea.

"We want the June 2016 referendum result to be respected and implemented," she declared.

"A majority of people throughout the United Kingdom voted to take back control of their money, laws and borders. Whilst many in Brussels may not agree with the referendum outcome, the result must be respected."

The EU's proposed backstop would see Northern Ireland effectively remain in the customs union and single market while the rest of the UK shifts away from Brussels' rules, something the Prime Minister has already said would be completely unacceptable as it would break up the UK.

"As we leave the EU, we should do so as one nation,” insisted Mrs Foster.

"The United Kingdom single market must be protected with no new borders between Northern Ireland and Great Britain being created. From day one this has been the DUP's only red line…recognising that Great Britain is Northern Ireland's biggest market,” explained the MLA for Fermanagh and South Tyrone.

Earlier as Westminster prepared to return to business on Tuesday following the conference recess, Downing Street played down talk of a Brexit breakthrough at next week’s EU summit.

Optimistic noises from Brussels have raised hopes that the EU27 and the UK are on the verge of an historic deal at the European Council on October 18 and 19. One diplomat claimed there was now “almost closure on all issues” while Simon Coveney, Ireland’s Deputy Prime Minister, said a Brexit deal was “90 per cent” completed.

However, No 10 went out of its way to dampen down expectations with the Prime Minister’s spokesman saying an agreement could be done “this autumn,” which appears to push back any hope of agreement being reached to mid-November at the earliest.

When it was suggested that the lack of public information from the UK’s side on how the talks were progressing could be regarded as a good sign as it did not want to say anything too fulsome at such a sensitive stage, the spokesman replied: “We have always said that we are working hard for a deal this autumn and that continues at pace.

"It's worth me pointing out that there is a difference between people talking optimistically about a deal and a deal - including both a withdrawal agreement and a future framework - actually being agreed.

"There remain big issues to work through and, as the PM has said, this will require movement on the EU side.

"There can be no withdrawal agreement without a precise future framework," he added.

Meanwhile, a grinning Jean-Claude Juncker, the European Commission President, appeared to mock Mrs May when he performed a little dance while preparing to give a speech in Brussels. Later his spokesman insisted Mr Juncker’s dance moves were “not directed at anyone” and that the Commission President had "great respect" for the PM.

Elsewhere, analysis of a series of polls found most voters now wanted the UK to stay in the EU. Remain had an average four-point lead during 2018, a reversal of the gap in the 2016 referendum.