Government papers from 1997 have been declassified to reveal that the former Labour Prime Minister thought it would be an 'excellent idea' to make the drastic move.
Shortly after Blair took office, a memo was sent 'following up earlier informal discussions about the possibility of an English Premier League football club relocating to Belfast'.
It was believed that having a Premier League club in Northern Ireland would be the best way to unite a divided city.
Wimbledon was chosen as the club to make the move, taking the Dons from south London to the Northern Irish capital.
It was also suggested that the club's name be changed to Belfast United, as well as building a 40,000-seat stadium.
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The private sector would fund most of the project with a location picked on either Queen's Island in east Belfast or the North Foreshore in the north of the city.
Blair had responded by saying it 'would be excellent if Wimbledon were to move to Belfast and we should encourage this as much as possible'.
While the story was leaked to the Belfast Telegraph, it garnered local opposition with many believing it would kill the game in Northern Ireland.
Alistair Campbell, who was Downing Street's chief press secretary at the time, did make a note of Wimbledon owner Sam Hammam's intentions.
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It was denoted that Hammam had 'explored the possibility of moving Wimbledon to Dublin' but wanted to know how serious such a plan was.
In July 1998, a few months after the Good Friday Agreement had been signed, Blair gave his personal support for the proposals.
A month later, another bulletin emerged noting the Irish football authorities strong resistance to the idea with the matter at a 'delicate stage'.
By the time of the next exchange in April 1999, there had been little progress made on the idea.
That is despite TV presenter Eamonn Holmes trying to drum up support from the public, as well as three local newspapers.
Eventually, the plans were shelved but Wimbledon would go on to move location anyway in 2004 when they relocated to Milton Keynes and were renamed as MK Dons.
A fan-led successor club was created in its place, going under the bame of AFC Wimbledon, who are currently in League Two.