The Taoiseach has warned that some jobs and some businesses may not be saved in the event of a no-deal Brexit at the end of next month.
Leo Varadkar also told the Dáil that there "hasn't been an enormous take-up by businesses" of a number of schemes set up by the Government to help mitigate the impact of Brexit.
He was answering Dáil questions from Labour Party leader Brendan Howlin, who said the time had come for the Government to "give clarity on the specifics of Brexit preparations".
Mr Howlin asked how much funding would be made available to sustain jobs in the short and medium term, and how much money would be made available from the European Union in the event of a no-deal Brexit in six weeks' time.
"The British government was forced, as you know, to publish its Yellowhammer report on the possible effects of Brexit," he said.
"Do you think, Taoiseach, it is now time for your Government to publish its own detailed clear analysis on the impact for every sector of our economy of a hard Brexit?"
Mr Varadkar responded that Budget 2020 was yet to be agreed and that the details would be announced in three weeks' time. But he said the "prudent thing to do is to prepare the Budget with a pessimistic scenario".
He said there would be a "substantial package" in the Budget to support businesses that are vulnerable, and that while most will come from the Government's own funds, some will come from the EU.
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"I need to be honest with people as well," Mr Varadkar said. "If we end up in a no-deal scenario it will be damage limitation and there may be some jobs that can't be saved and some businesses that regrettably can't be saved.
"But we will put together a package that will be significant, that will be meaningful and will allow us to save those jobs and business that are viable in the long term and that have been made vulnerable as a consequence of Brexit."
The Taoiseach also told the Dáil that the Government does not have any document similar to the British government's Yellowhammer.
However, he added that it had produced "all that information already" in the Brexit contingency plan document published in July, and in the summer economic statement.