Japan's chief government spokesman has announced that unidentified flying objects (UFOs) exist.

Earlier, in response to a question from an opposition lawmaker, the Japanese government issued a statement saying it could not confirm any cases of UFOs.

It is the sort of question politicians dread but, under Japanese rules, are unable to ignore.

A member of the opposition asked the government what its policy was to deal with UFOs.

The Japanese civil service swung into action.

In a statement it said that should a flying saucer be spotted in the country's airspace, a fighter would be scrambled to attempt visual confirmation.

But it emphasised that the government was not aware of cases where a UFO from space had been discovered.

The document revealed that Japan has not yet planned what to do should aliens arrive here.

The government's chief spokesman Nobutaka Machimura drew laughter from reporters when he admitted that this was a "stereotypical" response from the bureaucrats.

Perhaps with his tongue a little in his cheek he insisted that he believed UFOs did "definitely" exist.

Questioned about the existence of alien spaceships, Japan's Prime Minister Yasuo Fukuda thought about it and then answered carefully.

He said he had "not yet confirmed" whether they existed.

The conspiracy theorists will note that the answer was not a "no".