Proposals released by the National Archives on Friday reveal that 5.5 million Chinese people could have been moved to a newly built "city state" between Coleraine and Londonderry in the 1990s.
The 1983 government file called "Replantation of Northern Ireland from Hong Kong" reveals British officials thought the answer to all their problems would be to relocate millions of Chinese residents to Northern Ireland at the height of the Troubles.
The suggestion was made by Christie Davies, a sociology lecturer at Reading University.
The academic said that a city state should be established in Magilligan, between Coleraine and Derry, because the colony’s population would have no political future after the territory reverted to Chinese rule in 1997.
Davies believed the move would revitalise the local economy as well as save Hong Kong, which had "no future on its present site".
George Fergusson, an official at the Northern Ireland office, was inspired by the proposal to "transplant" Hong Kong to Northern Ireland and in a memo to his colleague in the Foreign Office he wrote: "At this stage we see real advantages in taking the proposal seriously".
David Snoxell at the Foreign Office replied: "My initial reaction, however, is that the proposal could be useful to the extent that the arrival of 5.5million Chinese in Northern Ireland may induce the indigenous peoples to forsake their homeland for a future elsewhere."
There is just one problem with the proposal: Closer inspection of the official document reveals the word "spoof" scrawled on the front.
Mr Snoxell, author of one of the two documents in the Hong Kong/Northern Ireland file, told BBC Radio 4's Today programme that it was "absurd" that people were taking the proposals seriously, adding: "It was a spoof from start to finish."
While it is refreshing to know that civil servants in the 1980s had a sense of humour - especially during a difficult time - it makes it all the more sadder that an occurrence would be so rare in today's bureaucratic society, Mr Snoxell told the programme.
He added that he "can't possibly see" how people have taken what was intended to be a joke so seriously.
While many failed to realise that the document was just a light-hearted exchange between colleagues, others embraced the April Fools-like prank.