London mayor Ken Livingstone has said the Greater London Assembly will enforce a blanket ban on all office schemes within 10 years unless the £10bn Crossrail proposal is given the go-ahead.
Speaking last week at an industry event in central London, the mayor said London would not be able to accommodate any more office developments without a new, substantial transport scheme.
He said: "Without Crossrail there would be a blanket refusal of development in the city. Our transport infrastructure would not be able to cope without it."
A GLA spokesperson added that to act in 10 years would be too late. She said: "This needs to start happening soon."
The Crossrail Bill is currently before a commons select committee.