Irish premier Leo Varadkar said he hopes Jeremy Corbyn will show leadership and come up with a compromised Brexit plan with Theresa May.
The Taoiseach said that Prime Minister’s offer to engage with the Labour leader on Brexit was “timely”.
Speaking in the Irish parliament, Mr Varadkar said: “I don’t know if Mr Corbyn will rise to the occasion, whether he will show leadership and be able to come up with a compromised plan with Prime Minister May.
“I hope he does, but we will see if that happens in the next couple of days.”
Mrs May was meeting the Labour leader in her Commons office in the hope of agreeing a position which can win a majority within the next few days, allowing her to request a short delay to Brexit at next week’s summit.
Mr Varadkar also said that the growing frustration among a number of EU countries over Brexit “is worrying”.
He added: “There is a real concern that if the UK stays in the EU beyond the date of the European elections and doesn’t hold the European elections then there is a risk parliament will not be properly constituted.
“Therefore any decisions made by the European Parliament, whether on legislation, on budgets, on the appointment of a new Commission and Commission President, may not actually be valid.
“There’s a lot of frustration among the majority of countries that aren’t going to be adversely affected by Brexit, that the concentration on Brexit is taking us away from other important issues and other important matters.
“That is worrying for us.”
Speaking about his meeting with French President Emmanuel Macron in Paris on Tuesday, Mr Varadkar added: “I have to say I am really heartened by the enormous support that France continues to demonstrate towards Ireland and, as (Mr Macron) said himself, that Ireland would never be abandoned by France or by the EU.
“Whatever issues arise, if there is no deal, they are very much seen as shared problems, ones that Ireland will try to resolve with our partners in France and the European Commission.
“It’s not a questions of a big stick or us being put under undue pressure, but there are reasonable questions being asked as to how we will protect the integrity of the single market and the single union.”
Mr Varadkar is to meet German Chancellor Angela Merkel in Dublin on Thursday.
The Taoiseach also said that the backstop will ensure the border between Northern Ireland and the Republic of Ireland is “tariff free, friction-fee, quota-free and bureaucracy-free”.
“I don’t know for certain that it’s possible to come up with an alternative that does that other than the UK remaining in the EU or staying in the single market and customs union, but we will do everything we possibly can to avoid the emergence of a hard border” he added.
“We know that some things can be done remotely, like the collection of tariffs and customs duties.
“All we can do now is explore options without knowing what is going to happen and that is what we are doing.”