The organizers of a massive anti-war protest have been banned from marching down Whitehall during the visit of President Bush next week.

The closure of Whitehall to demonstrators during the President’s three-day stay in London comes amid arguments over who should pay for the costs of policing the visit.

The Stop the War coalition, which is organizing a march from Trafalgar Square on November 20, said police were insisting demonstrators did not go through Parliament Square and Whitehall.

"It is an outrage that the most unwelcome guest this country has ever received will be given the freedom of the streets while a movement that represents majority opinion is denied the right to protest in the area which is the heart of government", said Lindsey German, convenor of the Stop the War Coalition.

Mayor Ken Livingstone this morning said millions of pounds will be spent on security during George W. Bush's state visit, which begins on November 19, and the city itself will have to pay.

Scotland Yard announced last week that police leave was to be cancelled during the American president's three-day visit, to allow for heightened security measures.

Asked this morning who would pay the possible £4million pound bill to keep Mr Bush - a potential target for Islamic extremist terrorists - safe, Ken Livingstone told assembled journalists it would come from the Metropolitan Police budget.

Diplomatic and royal protection was 'always an issue over which we haggle every year' with central Government, the mayor said.

"There's nothing unique about it. The Metropolitan Police budget always bears the cost."

Eric Ollerenshaw, Leader of the London Assembly Conservatives, said President Bush’s visit would be a full State occasion and the Government should be footing the bill, rather than the London taxpayer.

Mr Livingstone was also questioned over media reports that the president's officials had been pressuring Met commissioner Sir John Stevens to 'shut down central London' during the visit.

The mayor praised Scotland Yard's 'subtle' security measures - and pointed out there had not been a successful attempt to assassinate a Prime Minister here for 190 years.

"I'm very confident that the commissioner is working very hard to achieve a balance here," he said.

"There'll be freedom to protest, so long as it's peaceful."

Ken won't be joining the protesters on the streets himself, however. Rather, he has organised an evening protest party at City Hall, to which prominent dissenters to, and opponents of, Mr Bush and Mr Blair's war on Iraq will be invited.