Ireland face battle for World Cup
South Africa and the United States are expected to pose the greatest threats to Ireland's £100million bid to host Rugby World Cup 2023.
The Irish Rugby Football Union (IRFU) has confirmed an all-Ireland bid to stage the world contest in nine years' time.
The Northern Ireland Executive and Irish Government are underpinning the joint bid to secure rugby's global showpiece.
Chief executive Philip Browne said the IRFU and two Irish governments will expect to commit £100million to underwrite the possibility of staging the tournament.
"It has been out there that South Africa has stated an interest, Italy has bid in the past and stated an interest again, while Argentina has stated interest too, and also the USA," said Browne.
"We are under no illusions it's going to be competitive and we have to put our best foot forward.
"At this stage we haven't had to tender documents, we won't get those for another 12 months or more.
"For the Japan World Cup the guarantee tournament fee which has to be paid to Rugby World Cup is £96million.
"One assumes we are going to have to pay at least that, probably more."
Governing body World Rugby will not officially launch the bidding process for Rugby World Cup 2023 host status until next year, and have not even finalised a timeline for applications.
Ireland are the first nation to launch a bid for the 2023 tournament, but must now await further instruction from World Rugby on when to make any official tender.
World Rugby expects the 2023 hosts to be selected in 2017, leaving Ireland quick off the mark in acclaiming their intentions.
"This is an exciting announcement that further underscores the enormous prestige, appeal and benefits of hosting Rugby World Cup for both unions and governments alike," said a World Rugby spokesman in response to Ireland confirming their intentions so quickly.
Ireland's bid will be for sole staging of the tournament, and will not include any help from the likes of the Welsh or Scottish Rugby Union.
Dublin's Aviva Stadium, Ulster's Kingspan ground at Ravenhill and Limerick's Thomond Park will form the centrepiece venues.
Ireland's bid will also draw upon a host of Gaelic football stadia, with the 82,300-capacity Croke Park in Dublin at the forefront of that collaboration.
Political administrations in Ireland's north and south have given the bid the green light after a 10-month preliminary assessment exercise.
Irish premier Taoiseach Enda Kenny, Stormont's First Minister Peter Robinson and Deputy First Minister Martin McGuinness joined IRFU boss Browne to announce the bid in Armagh on Friday.
England will host next year's World Cup before the tournament descends on Japan in 2019, with World Rugby making good on long-held promises to grow the game beyond traditional heartlands.
South Africa staged one of the most memorable tournaments in 1995, the hosts holding off New Zealand to claim glory under the jubilant and politically-poignant scenes of Nelson Mandela proudly sporting a Springboks shirt.
New Zealand held the inaugural 1987 tournament, repeating hosting duties in 2011, while England will become the second nation to claim the honour twice, with 2015 following 1991.
World Rugby could well aim to send the 2023 tournament back to a traditional rugby hotbed, after the 2019 shift to Japan: and that would leave South Africa strong contenders.
The rugby-mad nation received a huge infrastructure boost for the FIFA football World Cup staged in 2010, so would argue much of the preparation work is already in place.
Rugby's rapid rise in America was cemented by New Zealand's decision to face the US Eagles at Chicago's Soldier Field en route to their November European tour.