Failing to address the transport needs of London's poorest communities could provoke riots, according to the city's transport commissioner.
Speaking to the Guardian, head of Transport for London (TfL) Sir Peter Hendy said there could be social unrest if the capital's low-paid workers - many of whom live on the outskirts of the city - are unable to commute to work.
"If you're not able to increase transport capacity, and people find accessing work impossible, you risk social unrest. You can expect trouble," he warned.
Mr Hendy said that, without progress on new rail lines, the city will face "overwhelming" overcrowding on its congested transport networks by 2030.
Although extensive tube upgrades have been made and £14.8 billion spent on the Crossrail project, London's spare capacity could soon be exhausted, as a rapidly expanding population means an additional six million trips will be made in the capital each day by the end of the next decade.