The windows of high-speed trains from Kent are to be blacked out during London 2012 to prevent any risk of rail passengers mooning at or making obscene gestures to VIPs or foreign tourists near Olympic sites.

Games organisers and train operators say they are introducing the cover-up following an official request from the International Olympic Committee (IOC) after its members expressed fears that revellers on trains leaving St Pancras might "insult" overseas visitors, games officials and dignitaries because the high-speed train lines run so close to the Olympic Park and other 2012 venues in east London.

The fear is that unruly passengers on high-speed trains heading out of the capital towards Kent in the evening, having been to pubs or bars after work, might think it was funny to make obscene gestures at Games-goers.

The London Organising Committee of the Olympic Games (LOCOG) today (April 1) issued a statement saying the "black-out" was "regrettable", but "understandable".

A LOCOG spokesman said: "We are responding to a request by the IOC inspection team that recently visited London to check on our progress regarding not only venue building work but ancillary activities related to the smooth running of the 2012 Games.

"Sadly members of this inspection team were mooned at by a group of drunken male passengers on a high-speed train as it passed through Stratford International Station where they were waiting on the platform for a train to take them to St Pancras where a coach was picking them up to take them to their hotel in central London.

"The inspection team members said they had been embarrassed and intimidated as two-fingered gestures were also made towards them as the train sped past.

"As a result of this unfortunate incident we have been contacted by the IOC's protocol committee who have requested that all high speed train windows be blacked out for the duration of the Games and we have reluctantly agreed. We have therefore asked Southeastern trains to comply with this request.

"We stress that this move will only be for the 17 days that the Games are taking place and the black-outs will be removed from the windows the day after the closing ceremony. The cost of the window cover-up will be met from our special contingency fund so there will be no cost to UK taxpayers.â€

Southeastern trains said today (April 1) that they had agreed to the introduction of black-outs on its entire high-speed train fleet and were now urgently putting out tenders for the work on the windows to be done in advance of the opening ceremony.

A Southeastern spokesman said: "It's a very unusual request but one we are happy to go along with to ensure international harmony and prevent any possibility of visitors to this country being insulted by the antics of a mindless few.

"We apologise to our regular customers and commuters for having to take these measures as it will mean their vision on daytime journeys will by necessity be impaired but we are confident they will understand the reasons why and we will make sure that lights in all carriages stay on at all times as a necessary health and safety measure.

"We would sooner introduce the blacked out windows as a safeguard rather than run the risk of overseas visitors leaving this country feeling slighted because they have suffered a bad visual experience."