One in nine police officers in England and Wales will be protecting George Bush on his state visit to Britain, which begins today.
Ten thousand more police officers have been drafted in amid rising concerns about the threat from terrorists and the scale of anti-war demonstrations. That brings to 16,000 the number of policemen and women who will be deployed during the four-day trip.
The bill will run to at least £7m, and the British taxpayer will pay for it.
The Metropolitan Police announced that it was boosting the numbers of officers on duty in London from 5,000 to 14,000.
The unprecedented security operation, which begins when the President arrives in London this evening, is partly in response to new intelligence that indicates violent anti-Bush demonstrators are travelling from continental Europe to protest in the capital.
Police also believe the national rally through London on Thursday will be far bigger than previously thought, with in excess of 100,000 now expected. Anti-war protesters were yesterday given permission by the Met to march down Whitehall, close to Parliament, having been earlier denied that route by Scotland Yard.
Anti-terrorist specialists are also growing increasingly concerned about possible al-Qa'ida attacks. This fear has been heightened by the bombings of two synagogues in Istanbul, which killed at least 23 people and wounded 300 on Saturday.
As well as the massive police operation in London, around 1,300 officers will be on duty when President Bush has lunch with Tony Blair and a group of residents in the Prime Minister's Sedgefield constituency on Friday.
All police leave has been cancelled in Durham Constabulary and officers from neighbouring forces will be drafted in as part of an operation costing £1m. The cost of the Metropolitan Police's deployments are expected to be in excess of £5m, while up to £1m is being spent on extra security at ports and airports.
On the eve of the American President's state visit, Mr Blair said he stood by the decision to invite Mr Bush to Britain.
Opposition to the President's visit appears to be growing daily. Concerns about the scale and intensity of the anti-war demonstrations prompted Scotland Yard to announce yesterday that they were almost tripling the number of officers on duty over the four-day period. A police source also disclosed that a number of anarchists and other extremists were travelling by train and ferry to Britain and were expected to take part in "ad hoc" violent demonstrations in London. The troublemakers are not expected to take part in the official Stop the War Coalition rally, which won permission yesterday to march past Parliament, bearing right along Whitehall and congregating in Trafalgar Square. At first the police had wanted to use an ancient law to forbid marchers going past Parliament. Jeremy Corbyn, a Labour MP who took part in the negotiations, said: "The march is going to be huge, very well stewarded and very well ordered."
Sir John Stevens, the Commissioner of the Met, has promised not to shield President Bush from"embarrassing" demonstrations. Deputy Assistant Commissioner Andy Trotter, who is in charge of policing the demonstrations, said the decision to increase the number of officers on duty to 14,000 had been taken primarily because of security concerns. "We're on a very high level of alert at the moment - we obviously have the visit of the President coinciding with that and we've got to make sure that London is kept safe and the visit goes well.
"At the same time we're concerned about disorder, not only the potential for disorder from the march itself but there will always be other opportunities over the few days of his visit and we've got to make sure we've got sufficient resources to deal with that." The police also remained "very concerned" about the level of threat posed by al-Qa'ida.
Mr Bush will be privately greeted by the Prince of Wales on his arrival this evening and will be the guest of the Queen at a banquet at Buckingham Palace on Wednesday.
On Thursday, the President will lay a wreath at the Tomb of the Unknown Warrior before talks with the Mr Blair. He will also meet relatives of British victims of the attacks on 11 September as well as servicemen who fought in Iraq.
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