Ministry of Defence staff recorded sightings of alien craft over Wallasey Town Hall and a saucer-shaped Unidentified Flying Object (UFO) hovering over Waterloo Bridge, it has been revealed.

Files detailing hundreds of sightings of unexplained objects in the skies above Britain have been opened to the public for the first time.

The information was considered sufficiently important for a form to be produced which is kept by police stations and airbases ready to record details of such reports.

Briefing documents for government ministers facing questions about policy on unidentified flying objects also form part of the release at the National Archives in Kew.

But the Ministry of Defence (MoD) was not investigating the possibility of visitors from outer space making a stop at Earth. Defence intelligence staff were more interested in checking that UFOs were not in fact signs of earthly covert spying missions by other countries.

Nick Pope, who worked for the MoD for 21 years and was responsible for investigating the sightings said: “While there’s no evidence of little green men in these files, they should be of immense interest to sceptics and believers.

“Most of the UFO sightings here are probably misidentifications of aircraft lights and meteors, but some are more difficult to explain, and include UFOs seen by police officers and pilots, and cases where UFOs have been tracked on radar.”

Eight files have been released after a Freedom of Information request by UFO researchers. Over the next four years more than 150 files will be thrown open.

But those hoping for proof of little green men will be disappointed.

An MoD memo, written in 1983, sets out their position very clearly. “The sole interest of the Ministry of Defence in UFO reports is to establish whether they reveal anything of defence interest (e.g intruding aircraft). Reports are passed to operations staff who examine them as part of their normal duties.”