Over £100 billion of investment, from both the public and the private sector, needs to go into the capital's transport, housing, health, and education services over the coming 15 years, according to research carried out for London First in the run up to the chancellor's comprehensive spending review.

This investment would allow London to maintain its world city status, and to continue to compete with Tokyo and New York.

Forum Response: London First

Jo Valentine, chief operating officer of London First, told ePolitix.com: "London currently contributes of the order of £20 billion a year net revenue to the rest of the UK. If the UK were a company, London would be its brand leader.

"We want to see a London in 2015 where the three million plus journeys a day on London Underground are safer, cleaner and more reliable, where citizens and visitors enjoy better buses, more reliable trains and less congested roads.

"We want London's population growth to have been matched by increased capacity and better facilities in the capital's schools and hospitals. All these extra people will need homes.

"This vision may seem remote - but the challenge is not insurmountable. £100 billion - or £7 billion a year - is achievable. Annually it represents only six per cent of London's GDP. Nevertheless, historic and current investment is nowhere near that figure.

"We recognise that even record levels of planned public sector investment will not be sufficient to achieve £100 billion. There is therefore a clear and significant role for private sector investment which could contribute half this amount if the right environment is created by the government.

"However that environment will not be created by assuming that the private sector will pay for everything.

"There must be a genuine partnership with the government committed to finding its share of the increased investment that is needed."