French authorities have denied European media reports that a mobile phone video footage was found at the crash site of the Germanwings plane.

According to the media reports, the video purportedly showed the final moments inside the cabin of the Airbus A320 before the plane crashed into a mountainside in the French Alps last week, instantly killing all 150 people on board.

A French police official has categorically denied that any mobile phone footage was discovered by investigators at the site and told CNN the media reports were "completely wrong" and "unwarranted", according to AFP news agency.

The video, reportedly found amid the wreckage of the plane, allegedly captured the sound of terrified passengers screaming and crying 'Oh, God' as the plane plunged into the mountainside some 100 km north of Nice.

The clip, said to be just a few seconds long, was reportedly retrieved from a memory card found at the crash site by a source close to the investigation.

According to French magazine Paris Match and German daily newspaper Bild the authenticity of the video footage was "unquestionable".

Bild and Paris Match said on Tuesday their reporters were shown the video after it was reportedly  found on a memory chip that could have come from a mobile phone inside the ill-fated plane.

Marseille prosecutor Brice Robin, who is one of the lead investigators of the crash, said investigators were not yet examining mobile phones found at the crash site, and he was not aware of footage from phones having been recovered, according to the BBC.

Anyone with footage "must hand it over immediately to investigators," AFP news quoted Robin as saying on Wednesday.

A transcript from the plane’s cockpit voice recorder suggests co-pilot Andreas Lubitz, 28, has deliberately locked the captain out of the cockpit before sending the aircraft into a steep plunge and crashing it in the French Alps.