The Labour Party leader warns there will be chaos at Ireland's ports in the event of a no-deal Brexit.
It comes after the Fianna Fáil leader Micheál Martin claimed Ireland isn't nearly ready for such a scenario.
Next week a new British Prime Minister will be elected, with both candidates saying they aren't afraid of a crash-out Brexit.
Labour leader Brendan Howlin says that crash will also impact things here:
"If we have to check every food product that goes through the Port of Dublin - it will be chaotic," he said.