Updated 12:55

A spokesperson for the Tánaiste has again warned that there will be no Brexit deal without a legally binding backstop preventing any return to a hard border in Ireland.

The statement comes after The Sunday Times reported that a deal keeping the entire UK within a customs union with the EU for a period of time after the official Brexit date was close to being agreed.

The paper reported this morning that the EU is now willing to include the “bare bones” of the arrangement within the Withdrawal agreement – something it has previously warned was not legally possible.

The Irish version of the paper reports EU sources as warning that the deal is dependent on the UK signing up to a Northern Ireland specific backstop that would come in to force if the wider agreement breaks down in later years.

The warning does not appear to have been included in the UK version of the report, which suggests that the breakthrough means that a backstop treating the North differently to Britain "may not be required."

Backstop

In his statement this morning, Simon Coveney's spokesperson said: “The UK has given written commitments last December and March that the Withdrawal Agreement will give a legal guarantee of no return to a hard border in Ireland in any circumstance - This is the backstop.”

He noted that the UK agreed in March that the backstop would remain in place “unless and until” a long-term future trading relationship that “eliminates any need for border infrastructure or related checks and controls” is in place.

He said the EUs support for Ireland “has been and remains unwavering” and warned that the UK must deliver on its commitments before negotiations on future relations can begin.

"Running commentary"

“The negotiators are working hard and a running commentary isn’t helpful,” he said. “Today’s Sunday Times piece is obviously aimed at a UK audience.”

“Donald Tusk, Michel Barnier, Jean Claude Juncker and indeed Theresa May herself have all said there will not be a deal without a legal guarantee of no hard border in Ireland.

“While we too hope the Northern Ireland backstop will never be required to be used - it will be required to be written down in legal text as committed to by the UK in order to have a Withdrawal Agreement.

“We hope a deal can be done but we’re not there yet.”

The Sunday Times report claimed that plans for a future economic partnership between the EU and the UK are far more advanced than had previously been disclosed – with a 50 page document to be published in the coming weeks.

It said that Downing Street now believes enough progress will be made in the talks this week for a special EU Summit to be called later this month.

UK Prime Minister Theresa May leaving 10 Downing Street, London, 31-10-2018. Image: Stefan Rousseau/PA Wire/PA Images

“Speculation”

This morning however, a Downing Street spokesperson told the Reuters news agency: “This is all speculation.”

“The Prime Minister has been clear that we are making good progress on the future relationship and 95% of the withdrawal agreement is now settled and negotiations are ongoing.”

It comes as more than 70 UK business leaders joined forces to call for a second Brexit referendum.

They have signed a letter warning of the possible economic damage of a ‘destructive hard Brexit.’