The Metropolitan police has increased its stocks of baton rounds, also known as plastic bullets, to more than 10,000 as a result of the August 2011 riots, the force has confirmed.
Figures released by Scotland Yard show the Met now has the largest stockpile of plastic bullets it has held for many years. Three years ago its stockpile was 6,424 but figures from last December show the Met now keeps 10,024 baton rounds.
The Yard said it had increased the number of officers trained to deploy baton rounds to 300. It said baton rounds are bought once a year and stocks were obviously at their highest at the time of ordering.
In a statement the force indicated it was now in a position to be able to deploy baton rounds should a security situation require it in the runup to the Olympic Games.
"Last summer we were criticised for not having sufficient numbers of specialist trained and equipped officers to make this tactical option available," the force statement said. "Training has increased over recent months as a sensible precaution to ensure that we can make this happen. Before an event they require the authority of an assistant commissioner and during an event they require the authority of at least a commander."
Scotland Yard considered using plastic bullets at the height of the August riots last year, but after coming close to authorising their deployment senior officers pulled back from the decision ? partly because there were not enough units available to deploy them safely and proportionately ? and instead used vehicles to disperse rioters in south London.
A police spokesman said: "Baton rounds are one of a number of operational tactics available to police and they are only considered in the most extreme situations to reduce the threat posed by specific individuals in order to protect life, to prevent serious injury or prevent significant damage to property during serious public disorder."
The force said baton rounds had been placed on standby on a number of occasions in London but had never been used.
Rubber and then plastic bullets have been deployed in Northern Ireland since 1969 and are still in use. Known as attenuated energy projectiles, plastic bullets are about 15cm long. Unlike rubber bullets, which are fired into the ground first, plastic bullets are fired directly at someone in a riot situation.
The police are supposed to fire at the individual's legs but 17 individuals, eight of them children, have been killed since 1969 with rubber and latterly plastic bullets. Many of those killed were hit in the head or chest.
During the riots the president of the Association of Chief Police Officers (Acpo), Hugh Orde, warned against their deployment against young people who were looting and rioting on the streets. He said they were not suitable for such public order situations and should only be considered during an insurgency when lives were at risk.
But the Met's review following the riots, titled Four days in August, said the force was developing more "assertive tactics" to tackle disorder, including the use of water canon and baton rounds.
The Met has been quoted more than £4m to buy three water canons for use during any future public disorder.
The review revealed that the Met twice considered using plastic bullets during last summer's rioting. The first time their deployment was considered was on the second night of riots, when trouble broke out in Enfield, north London and Brixton, in the south of the city. But senior officers held back, believing the would raise the levels of retaliation and increase the likelihood of some individuals using firearms.
On the third night, a Monday, when the most intense disorder took place, the force said it was not possible to mobilise the baton rounds quickly enough to south London in order to use them in a proportionate way.