London's Metropolitan Police said on Monday afternoon that there would be the largest ever exercise in the city to test security plans for the Olympic Games.

The major exercise will test the response of emergency services and the British government to a terror attack, which could occur during the Olympic and Paralympic Games, set to start on July 27.

The London transport system was the target for the most serious terrorist attack yet in London, on July 7, 2005, when 52 people were murdered by suicide bombers in four separate attacks on Tube trains and buses.

The attacks were timed for just one day after London was awarded the Olympic and Paralympic Games for 2012.

Under the exercise, emergency services and the government imagine that the attack has taken place on August 7 or 8, which are set to be the two busiest days of the Olympic Games, and that the Tube system and transport network had been targeted.

A disused former Tube station, Aldwych station, in central London will be the focus of the exercise.

James Brokenshire, Minister for Crime and Security at the Ministry of the interior, the Home Office, said, "We want to deliver a Games where the sporting achievement and the Olympic spirit is what people will remember - not the security."

"To ensure that happens we need to test our plans and this exercise gives us the opportunity to inform, reassure and build confidence in the UK's safety and security operation," Brokenshire added.

"We are determined to leave nothing to chance to deliver a safe and secure Games that London, Britain and the world can enjoy," Brokenshire continued.

Assistant Commissioner Chris Allison, National Olympic Security Coordinator, said, "This is part of series of exercises which we have run in the lead up to the Games, but this is the first with such a significant response from the emergency services on the ground. The initial incident will test the tactical response including evacuation the station, rescuing injured people and managing the crime scene."

Allison said that the exercise would go on to test how senior decision makers manage the impact of the incident, the investigation to catch those responsible and a range of issues such as travel disruption, protest and organized crime which may impact on the smooth running of the Olympic Games. Enditem