Ireland, competing with France and South Africa to hold the event on its own for the first time, completed a two-day review of what it has pitched as a politically symbolic proposal to play games on both sides of a border once beset by violence.
Brexit is especially disruptive for Northern Ireland because its border with the Republic is the UK's only land border with the EU, raising the prospect of tougher controls at the currently seamless border when the UK quits the bloc in 2019.
"I personally do not think it will be an issue because Ireland, Northern Ireland and the UK are going to have to find a resolution to the issues long in advance of the World Cup," bid chairman and former Irish deputy prime minister Dick Spring told reporters.
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"I have to say I have confidence in people's abilities to sort out any problems. Our relationship with Northern Ireland is too important to allow it to be impeded."
Unlike football, the national team in rugby is an all-Ireland selection and three stadiums in British-run Northern Ireland are among those being considered.
Ireland's Gaelic Athletic Association (GAA), which until 1971 banned members from playing or attending so-called "foreign games" like rugby, has also proposed using its stadiums for the World Cup, such as the 82,300-capacity Croke Park.
As well as meeting Irish Prime Minister Enda Kenny and President Michael D. Higgins, World Rugby officials were given a hurling clinic in the Dublin stadium by one of the Gaelic sport's most famous players, Henry Shefflin.
"The all island aspect is an extremely important aspect of our bid," said Spring, who as foreign minister in the 1990s played a role in negotiations that led to the 1998 peace deal that ended three decades of bloodshed in Northern Ireland.
"It hasn't gone unnoticed that rugby has been a sport that has had a unifying effect. Despite all the difficulties and troubles in that period from 1969, one team was still able to put on the green jersey."
The former rugby international said Ireland was in a good position to host the World Cup and would continue to make its case to voters, including during June and July's British and Irish Lions tour of New Zealand, before the final decision in November.
"It would be the most exciting thing to happen in my lifetime in terms of sport," Spring said.
(Editing by Toby Davis)
