This week’s Spending Review will require the chancellor to make difficult decisions. Cutting investment in transport in London would be a very false economy. With a population growing by 100,000 a year, continued investment is needed to keep not just Londoners but the Treasury’s tax take from the capital moving.

Parts of the Underground need urgent attention, as demand on already congested services is rising by 5 per cent a year and over-crowding so severe at some stations – such as Oxford Circus – that they are often forced to close their gates to passengers.

Much can be done: new signalling, track and trains on the over-crowded Piccadilly line would increase capacity by 60 per cent. Additional trains are needed on the Northern and Jubilee lines – now possible thanks to the success of previous signalling upgrades. And new bus links and upgrades to the Docklands Light Railway would help make space for passengers and serve new housing developments as the city expands to the east.

If London is to remain one of the world’s greatest cities to live and work, and to continue to generate substantial tax revenues for the Treasury, it needs a transport system that sustains its growth.

David Leam, infrastructure director, London First

Robert Elliott, chairman and senior partner, Linklaters

Inderneel Singh, managing director, Edwardian Hotels (incorporating Radisson Blu and May Fair brands)

Stephen Howlett, chief executive, Peabody

Michael Arthur, president and provost, UCL

Karen Shaw, director of research and enterprise, City University

Simon Baynham, property director, Howard de Walden Estates

Stephen Ashworth, partner, Dentons

Robbie Owen, head of infrastructure planning and government affairs, Pinsent Masons

Bill Moore CBE, chief executive, The Portman Estate

Robert Gordon Clark, executive chairman, London Communications Agency

James Turgoose, director of London, JBP

Nick Jopling, executive property director, Grainger plc

Reena Patel, partner, Wragge Lawrence Graham & Co

John Rhodes OBE, director, Quod

Bob Rothenberg, senior partner, Blick Rothenberg

Chris Osborne, chairman, FTI Consulting

Bob Weston, chairman, Weston Homes

Tim Hancock, managing director, Terence O'Rourke

Laurence M Ronson, founder, Ronson Capital Partners

Richard Patient, managing director, Thorncliffe

Karen Cooksley, partner, Winckworth Sherwood

Paul Williams, director, asset management, Derwent London

Michael Lowndes, executive director, Turley

Peter Vernon, chief executive, Grosvenor

Ciaran Bird, UK managing director, CBRE

William GS Jackson, chair, Central London Development, Cushman & Wakefield