The O2 arena is seen as smoke continues to rise from a Sony Warehouse, which was destroyed by arsonists in Enfield, in north London. REUTERS

The International Olympic Committee remains confident that the 2012 Olympic Games will proceed as planned, despite the recent disorder in London and across the UK.

Fears for the safety of participants and spectators forced the cancellation of England's international friendly against the Netherlands on Wednesday evening and may yet postpone the opening weekend of the English Premier League.

Widespread violence in the capital over the last three days spread to Manchester and the Midlands on Tuesday night, with rioters looting shops and setting cars and buildings on fire.

On Monday night, the unrest centred on Hackney, east London, close to the site of the Olympic Stadium that will constitute the centrepiece of the 2012 Games.

Critics have since questioned London's ability to guarantee the security of high-profile events at next summer's Olympic Games.

Nevertheless, the IOC says it retains belief in the British government and the Metropolitan police to safeguard the security of the Games.

"Security at the Olympic Games is a top priority of the IOC. It is, however, directly handled by the local authorities, as they know best what is appropriate and proportionate. We are confident they will do a good job in this domain," a statement from the IOC said.

However, the timing of the violence could not have been worse. With IOC executives due to arrive in the city this week to oversee test events for beach volleyball at Horse Guards Parade, the cycling road race and the marathon swimming event.

"There's no doubt that this is a very bad day, a worrying day, for Olympic organisers in London," Tony Travers, a professor at the London School of Economics, told the New York Times.

"They planned to protect London from conventional terrorism. But of all the things they might have thought might happen, I'd be surprised if civil insurrections was high up on their list of expected risk factors."

Yet officials insist local law enforcement is ready for every eventuality and stressed the rigorous preparation already underway across the city.

"A lot of detailed work has taken place regarding security plans for the Games and we will continue to review them together with the Met police and the Home Office over the coming year," a London 2012 spokeswoman told the Guardian.