Britain's 'all-UK' proposal falls short of EU demands, can form part of solution: Irish PM

"The UK is proposing that for a temporary period they would sort of stay in the customs union and that falls short," Varadkar told a government event to prepare businesses.

Britain's proposal that a so-called "all-UK" backstop provide an insurance mechanism to avoid a hard border on the island of Ireland falls short of EU demands but could form part of a solution, Irish Prime Minister Leo Varadkar said on Thursday.

"The UK is proposing that for a temporary period they would sort of stay in the customs union and that falls short," Varadkar told a government event to prepare businesses for the impact of Brexit.

"I don't think it's a non-runner, I think it's something that we can consider, something we're listening to. It might be part of the solution but I don't see it as an alternative to the (Northern Ireland-only) backstop and it would have to be on the basis that there would be a level playing field (between Britain and the EU)."