The Taoiseach has said he thinks the European Council would be open to granting a further extension to Article 50, but that this could not be "a licence for further indecision" in the UK over Brexit.
Speaking in the Dáil, Leo Varadkar said a clear plan is needed from British government.
He said: "My general sense across the European Council is that it is open to granting a further extension to the United Kingdom, but we don't want that further extension to merely be a licence for further indecision.
"We need a decision from the United Kingdom government and parliament. We need a clear plan."
Mr Varadkar also warned that there was a "real concern" that if the UK stays in the European Union beyond the date of the European Elections and does not hold elections, this could risk the European Parliament not being properly constituted.
He said that this could mean decisions of the European Parliament on issues such as voting for budget and a new commission may not actually be valid.
Mr Varadkar also said there was also growing frustration in the majority of EU countries that are not adversely affected, that the concentration on Brexit was distracting from other important matters.
He said while he did not want to comment on the internal politics of the UK, he hoped British Prime Minister Theresa May's offer to engage with Labour leader Jeremy Corbyn was "timely".
Earlier, Tánaiste and Minister for Foreign Affairs Simon Coveney said the latest Brexit developments were welcome and it was very unlikely the UK would crash out of the EU next week.
Last night, Mrs May said she aimed to ask for a further extension to the Brexit process to allow the UK leave the EU "in a time and orderly way".
She also offered to hold talks with Mr Corbyn.
Speaking on RTÉ's Today with Sean O'Rourke, Mr Coveney said Ireland would support the UK if it sought a short extension.
He said the arithmetic in Westminster has always meant that the only way forward is for the two largest UK parties to work together.
Mr Coveney said all of the options for the British Prime Minister were difficult, but she had done everything possible to gain support from her own party and the DUP, whose ten MPs prop up her minority government.
The offer to Mr Corbyn, he said, was a recognition that she needs to have the support of the Labour Party in order to leave with a deal.
Mr Coveney said Mrs May has shown leadership on the matter and is putting the interests of the country first.
He added that "we will have to wait and see" if the Conservative and Labour parties can reach a deal by the end of the week.
Mr Coveney said if a deal on a structured and managed Brexit could be reached then a two to four-year transition period would follow.
He said this transition was in the Withdrawal Agreement, which Mrs May has accepted will not be changed.
The Tánaiste said that while these developments were welcome, Ireland must still prepare for a worst-case scenario and the risk remained that the UK would crash out of the EU without a deal.