time is running out to find a solution to the Greek crisis before a default, Taoiseach Enda Kenny has said.
Speaking in Dublin Castle, at a meeting of the British-Irish Council, Mr Kenny said he feared a "Plan B" for Greece may be needed.
His remarks come ahead of Monday's emergency summit of EU leaders in Brussels, which has been called specifically to deal with the possible Greek default.
"We are getting closer to having to adopt a Plan B for Greece, and I am not sure where things are going," Mr Kenny said.
He said that at European Council meetings there had been strong support, encouragement and assistance for the Greek government in dealing with this serious problem.
"It is now getting very close to real crisis time. I note the comments from the minister [for finance, Michael Noonan] last evening that Europe is moving to a point where a Plan B may have to be considered," he added.
He said it was for that reason that the European Council was meeting on Monday. "I'm not sure what the outcome will be. I made the point to the Greek prime minister that stability is what the people of Greece need now. They need to put an end to the instability," he added.
Mr Kenny said European leaders were committed to seeing Greece stay within the eurozone, but said it was an exceptionally difficult situation. I'm not sure what extra can be decided on Monday, but I do hope we can resolve the situation," Mr Kenny added.
The Taoiseach said he and the finance minister were taking advice from the Central Bank and the National Treasury Management Agency as to the potential impact of a Greek default on October's Budget.
"We are taking advice from the Central Bank here and the NTMA in respect of that consequence. We don't have figures as to what that might mean," he said.
"For Greece a default would mean a very rapid social spiral - and that is why it is most important that the integrity of the eurozone be maintained.
"All of this argument is about the release of €7bn, which will only carry them through another number of weeks. After that, what is the consequence? Is there a third bailout? And, if so, what might the extent of that be," he said.
In relation to the North, First Minister Peter Robinson said there was no future for the Northern Assembly unless the Stormont House agreement was implemented.
Deputy First Minister Martin McGuinness said he, too, wanted to see the Stormont agreement implemented, but said difficulties remain.
He lashed out at the Tory-led welfare cuts in the North over the past four years.
Mr McGuinness also distanced himself from reports that he was about to resign over the Stormont House agreement impasse.
He said that any moves to withdraw welfare functions from Stormont by London would be unacceptable.