Irish premier Leo Varadkar has said the European Union (EU) is as one on the need for a border backstop in the Withdrawal Agreement.

The Taoiseach said the controversial issue was not just of concern to the Irish, as fellow EU leaders saw the measure as vital to protect the integrity of the European single market.

In Brussels for the second day of the European Council meeting, Mr Varadkar said he was “very satisfied” with the summit conclusions on Brexit which made clear the withdrawal agreement was not “up for renegotiation”.

The Taoiseach said he still believed a no deal was an “unlikely scenario” despite the EU ramping up preparations for such an eventuality.

“As Europe, we reaffirmed our commitment for the need for a backstop,” he said.

“An open border between Northern Ireland and Ireland can’t be a backdoor to the single market.

“That’s why European countries also very strongly support backstop. It is not just an Irish issue, it is very much a European issue as well.

“It is very much a case of the European Union being one-for-all and all-for-one.”

The backstop, which will come into effect if a wider trade deal between the UK and EU fails to materialise, will see Northern Ireland adhere to a range of EU regulatory rules in order to facilitate free-flowing trade across the border.

Prime Minister Theresa May is facing widespread opposition to the measure at Westminster amid claims it will undermine the integrity of the United Kingdom by creating an economic border between Northern Ireland and Great Britain.

Mr Varadkar said the issue could not be deferred to the trade talks post-withdrawal.

“It’s not just an Irish issue, it’s a European issue,” he said.

“It’s about protecting the peace, keeping the border open, also protecting the single market and making sure we answer this question of the Irish border now, so no side can use it as leverage in the future relationship talks, which we are willing to start as soon as the Withdrawal Agreement is ratified.”

The Taoiseach said while the EU was willing to offer “clarifications or explanations” to Mrs May, he reiterated that a renegotiation of the deal was not an option.