A Belgian UFO photograph that became a worldwide hit was faked with a piece of polystyrene, one of the people behind the picture has revealed more than 20 years later in a TV interview.

"You can do a lot with a little, we managed to trick everyone with a piece of polystyrene," said one of the forgers, identified only as Patrick, who says he pulled it off at the age of 18 with some colleagues.

"We made the model with polystyrene, we painted it and then we started sticking things to it, then we suspended it in the air ... then we took the photo," he said in an interview with French-language broadcaster RTL, which was transmitted late on Tuesday.

The photograph, taken in 1990, became a sensation after it was circulated around the world. It became known as Petit-Rechain picture, after the Belgian town where it was purported to have been taken.

It was closely associated with a period known as the "Belgian UFO wave," which involved a series of reports of UFO sighting between 1989 and 1990.

In one sighting in November 1990, which was later explained as a soviet satellite breaking up, dozens of people in Belgium reported a triangular object with three lights flying slowly and soundlessly, according to a Reuters report at the time.