Roadwork rubbish around Whitehall is cleaned up amid fear of G20 rioting

With world leaders arriving next Wednesday, authorities realised at the last minute that construction works were blighting the image of the city.

The clean-up comes as London braces itself for days of protests, beginning tomorrow with a Put People First march through the capital to a mass rally in Hyde Park.

On Wednesday G20 protesters will converge on the Bank of England on what is being dubbed Financial Fools Day. On Thursday activists will target the G20 summit itself, held at the ExCel conference centre in east London.

There are fears that discarded lumps of concrete, bricks, wooden stakes and scaffolding poles at construction sites could be used as weapons by some demonstrators intent on violence.

Whitehall and Parliament Square were this morning strewn with rubble from the major works which run between the Houses of Parliament and Trafalgar Square. New paving stones are being laid down in Whitehall for a 100-yard stretch outside Downing Street, while water pipes are being replaced in Whitehall and Parliament Square.

Government sources have told the Evening Standard that officials at the Cabinet Office and Department for Transport issued an order to clear up and close the works late yesterday.

The sites will now have a major clean-up in the next 24 hours to make them more secure - and spare embarrassment, with world leaders such as Barack Obama due on Wednesday.

The route of tomorrow's march, organised by the TUC and 120 other organisations, goes past the road and pavement works.

Wetsminster Council said today: "We have instructed all our contractors to be ready to secure all sites and clear them where necessary. As an additional precaution in the Whitehall area we will be stopping all street works for the duration of the summit and the area will be cleared and made safe."

Shadow home secretary Chris Grayling criticised the Government's hand-ling of the security preparations. He said: "There is definitely a fear that there will be significant protests across London next week. It is to the discredit of the Labour Government that preparations are happening so late."

Deputy Mayor of London Richard Barnes said: "It is foolish to leave potential weapons around protesters, particularly at a time when concerns are at their highest because of the G20."

In Whitehall today, commuters were unimpressed by the state of the roads and pavements.

Civil servant Margaret Philips, 57, from Twickenham said: "You'd think that with the President coming they'd have made this spick-and-span. It certainly looks a mess at the moment and I can't imagine that they will have it ready in time for Mr Obama."

Graffiti removal teams with Westminster City Council have been placed on high alert in case any racist graffiti referring to Mr Obama is daubed on walls where he is likely to pass.

Thames Water's £650million scheme to replace Victorian mains pipes has caused traffic chaos and is due to continue until 2010. A sign in Whitehall suggests the construction works there should be completed by 26 June.