Less than half of London's businesses expect to benefit from the Olympic Games, new figures reveal today.

Two-thirds thought the Games would benefit London but only 44 per cent expected a direct benefit according to the twice-yearly London Business Survey.

The Games are expected to generate £10billion for business and add £21billion to the economy but firms outside transport and construction, particularly small ones, still feel excluded.

Richard Lambert, director-general of the Confederation of British Industry, is expected to urge London's Olympics leaders - including Sebastian Coe, Olympics minister Tessa Jowell, and London mayor Boris Johnson - to make sure the Games had maximum benefit for all businesses.

At the CBI's 2008 business summit today he is due to say: "We should ensure the 2012 Games are a roaring success and deliver a lasting legacy.

"The business community needs to be as involved in the Games as it can. I urge those who are sceptical to look at how they can get involved, commercially and in the community, in the Games.

"Olympic organisers should ensure the opportunities are relayed to all businesses, regardless of size or sector."

The CBI is also anxious that the Games will help to regenerate east London and wants the Mayor and Government to promote employer-inspired training courses and develop more jobs.