Ireland will seek hundreds of millions of euros in aid from Brussels if Britain crashes out of the EU without a deal, the agriculture minister was quoted Thursday as saying.

"You're looking at hundreds of millions here," Michael Creed told the Irish Independent.

"Between the beef industry and the fishing industry we're talking mega-money."

With Westminster locked in stalemate over the painstakingly brokered draft Brexit deal, the possibility of Britain leaving the trading bloc in March without an agreement now looms ever larger.

The emergency aid for Ireland would aim to buttress sectors such as beef, dairy and fishing - those most exposed to customs and regulatory changes likely to arise if Britain severs all ties.

Nearly 80 per cent of Irish exporters deliver products to Britain, according to 2016 government figures. The country is also considered a vital "land bridge" to the European continent.

"There is a high level of awareness of Ireland's unique exposure to the UK food market," Creed said.

"I think nobody wants to talk about it right now because there is still a hope and expectation that a level of sanity will prevail."

But, he added: "In racing parlance the odds are slashed on a hard Brexit."

If Britain crashes out of the European Union on March 29, Creed said he hoped an EU grant would be approved at a Luxembourg summit of EU farming ministers in April.

On Thursday, the Irish cabinet is to discuss no deal contingency plans aired publicly for the first time before the Christmas break.

They include schemes for port overhauls, a fund for Brexit-specific tax staff and talks to preserve the island's integrated electricity network.

Up to 45 pieces of emergency legislation would be required - an agenda likely to bring all other Irish parliamentary affairs in early 2019 to a grinding halt.