A secret dossier has now emerged to reveal that British spies spent half a century to catch a UFO so they could use its alien technology to build superweapons.
Declassified files reveal the Government was concerned that the Soviet Union of China had impounded a UFO and were harvesting its secret to develop super-fast warplanes.
The cache of documents reveal between 1947 to 1997, intelligence services ran two UFO desks - one was a public-facing desk where people could phone in sightings. The real work was carried out in the background by spies set to investigate.
The UFO desks ran until 1997 by which time word had come from Whitehall that security services 'investigating 'X files stuff such as alien abductions' had become a diversion from their main duties.
A review was ordered to confirm the desk should be shut down, but also to determine whether anything had been learned over the years which could be useful to military.
After all these years, a report called UAPs (Unidentified Aerial Phenomena) in the UK Air Defence Region is part of three files running to more than 1,000 pages set to be released after being declassified.
They were held back from the UFO records earmarked for transfer to the National Archives as part of the Open Government project from 2008 to 2013.
But earlier this year, a complete set of redacted copies was sent to Dr Clarke ahead of their release to the National Archives, which is imminent.
The documents reveal the RAF expressed great interest in finding an UFO to help them come up with an innovative way of beating enemies during the Cold War.
Another air force commander feared the enemy may have already seized a UFO, writing: 'Monitor all reports in case in the future the hitherto unknown/not understood underlying phenomena is being exploited by another nation.
'An actual - or potential enemy - could develop a flying device with the characteristics that these phenomena seem to have.'
Spies were given given tips on what to look out for when identifying foreign objects. The unnamed commander wrote particular attention should be paid to any aircraft behaving 'like a UFO'.