BOB Blackman, London Assembly member for Brent and Harrow, and the Conservative spokesman on the Olympics, has raised concerns over revised budget negotiations.

The talks take into account escalating security costs and the claimed need to meet pressures to expend more on the regeneration and legacy aspects of the Olympic site.

The budget revision came a day after the Mayor of London said he felt it "not unreasonable" that London should contribute 10 per cent towards the cost of the games.

Mr Blackman said that given the shortfall could be as high as £2 billion, would Ken Livingstone find it unreasonable to ask London for an extra £200 million?

Mr Blackman said: "When we first saw the original budget, we were adamant in our opinion that it was unrealistic, and that problems would occur.

"We were dismissed as scaremongers, and reassured that the proposal was robust and the figures bullet-proof'.

"However, following this worrying announcement, everything that we predicted would happen - the escalation in costs - is happening, only at a far quicker rate than we feared.

"It is apparent that the actual bid document has fallen to pieces, in effect: not worth the paper it was written on. "

Ministers, headed by the Chancellor, Gordon Brown, and Tessa Jowell, are expected to make a decision within the next few weeks as to where the funding for the £2 billion increase is likely to come from, but the main worry, Mr Blackman said, was that a proportion of the burden will fall upon London taxpayers.

On Tuesday (October 24), Mr Livingstone said thaty Londoners shouldn't feel aggrieved at having to contribute 10% towards the cost of the Olympics, given the benefits the city would receive.

Mr Blackman said; "We simply cannot accept any possibility that this extra burden will fall exclusively upon Londoners, after all the whole of the country will benefit, and London already contributes disproportionately through levels of income tax.

"If the Mayor believes in not unreasonable for us to contribute 10% will we suffer an extra £200m now the costs have risen?"

"For this reason we remain committed to ensuring that the Olympic Bill currently going through Parliament contains a cap on the levels that London council tax payers would face - something which Mr Livingstone has always opposed."