A match between Rangers and Celtic in Belfast in which players would wear the jerseys of the opposing team was suggested to Tony Blair in the 90s.
The proposal was made by former No 10 adviser Alastair Campbell in the early days of the New Labour government.
Campbell wrote to the then-prime minister on April 12, 1998, ahead of the Northern Ireland Good Friday Agreement referendum – which took place the following month.
In a letter, disclosed alongside other documents now published by the Cabinet Office, Campbell suggested that it would be a “unique event”.
The former adviser claimed that the move would send out a message that would be “very powerful”.
He also told Blair that he had a “direct in” to Celtic, while stating that he would be able to get then-Manchester United manager Alex Ferguson to approach Rangers.
Mo Mowlam, who was the secretary of state for Northern Ireland between May 1997 and October 1999, and Donald Dewar, who was at that the time secretary of state for Scotland, were both copied into the letter.
The proposed match would have taken place weeks before Scotland kicked off their 1998 World Cup campaign in France.
In the note, titled, ‘Rangers v Celtic’, Campbell sounded out the idea.
He wrote: “An idea. What about organising a match between Rangers and Celtic, in Belfast, in the final days of the referendum campaign.
“It would be a unique event in its own right, but we could add to it by getting Celtic to wear Rangers strips, and Rangers to wear Celtic strips (though one or two of the Rangers players to my certain knowledge, may have difficulty with this).
“However, both in terms of raising publicity for the campaign, and in sending out a message, it would be very powerful.”
Campbell continued: “I have a direct in to Celtic, while I can get Alex Ferguson to approach at the Rangers end.
“Before I proceed, do you and Mo think it is worth pursuing even if, given end of season commitments, it may not be possible to get all the big names there? Let me know.”