"In a no deal scenario, while we will prevent physical infrastructure, undoubtedly the imposition of tariffs and the need to protect the integrity of the single market, to keep Ireland in the single market that we have been part of creating, will provide a disruption to the all-island trade which is something that we will all work intensively to avoid".
However, the Government insists that does not have to happen at the border and it is not planning for a return to customs posts.
And while the Contingency Action Plan Update says it is difficult to forecast the full impact on the Irish economy, it warns that small business will be hardest hit and tens of thousands of people could lose their jobs.
"Analysis of import volumes and commodity prices shows that NI businesses would have increased vulnerability to low-priced non-EU imports in the GB or NI market".
That is now increasingly unlikely as both Boris Johnson and his rival for the leadership of the Conservative Party, Jeremy Hunt, insist that the United Kingdom will leave the bloc with no deal on October 31 if they do not get rid of the backstop.
In a no-deal scenario, Ireland has pledged to impose the necessary checks to preserve its full participation in the European Union single market while avoiding any related infrastructure - a task Coveney said has not been easy to resolve in contingency talks with Brussels that began early this year.
The two candidates are expected to spar on five key areas: alternative exit deals and no-deal Brexit budgets, corporate and middle class tax rates, migrant quotas, benefit packages offered to immigrants and defence spending budgets.
Under a British government led by Hunt the poll predicted that the newly formed Brexit Party would win 23 MPs in the House of Commons, compared to no Brexit Party MPs if Johnson wins. For people living in border counties and in Northern Ireland, this will be really hard.
"There is no sugar coating of that message".