London business leaders will warn today about the risk of losing a "decade to indecision and delay" that could cost up to £18bn if a firm commitment is not made to Crossrail 2.
Jasmine Whitbread, the chief executive of London First, will say at the London Infrastructure Summit that without a firm commitment to keep the £31bn project on track, there is a risk of making the same mistakes that delayed Crossrail.
"Our choice now is whether we keep Crossrail 2 on track, or lose a decade to indecision and delay. We've been here before," Whitbread will say.
In 1994, Crossrail hit a red light when the Crossrail bill was rejected by parliament, with the government citing fears about public spending.
It took until 2004 for Crossrail to get back on track when the government committed to introduce legislation to support Crossrail and to work with TfL and business to develop a funding and financing package.
Crossrail 2 managing director Michele Dix has said that each year of delay could cost £1.8bn in construction costs alone, and Whitbread will warn today that "making the same mistakes could cost us up to £18bn".
While the project got a boost in July when the mayor and transport secretary Chris Grayling committed to working together on the next steps for Crossrail 2, there are still funding question marks that threaten to derail progress.
London had been asked to foot half the bill, but in the July update, the Department for Transport said this had to be met during construction. And time is ticking, with the Crossrail 2 previously saying they needed to get the go-ahead by the autumn, after the election extinguished hope of being able to progress with the project in May.
Grayling has said there is "no doubt" that London needs new infrastructure to support its growth, but "given its price tag we have to ensure that we get this right".
It comes as business leaders across the north and the capital have called for infrastructure investment across Britain.
The London Chamber of Commerce and Industry (LCCI) said this week it is in the best interests of the UK to avoid solely plugging investment into the southeast area.
LCCI policy director Sean McKee said:
It is interesting to note that the distance between Leeds and Liverpool is roughly the same as the whole length of London Underground’s Central Line - yet that northern journey can sometimes nearly take double the time.
LCCI is happy to endorse previous calls for a ‘Crossrail of the North’. The proposed cross-Pennine plans involve tunnelling – and the skills and experience from the new Elizabeth Line/Crossrail project in London could be put to good use to deliver practical connectivity.
He added: "As the UK faces into a post Brexit future, our economy will be much stronger if we create opportunities for jobs and future growth beyond the capital."
Meanwhile, the Greater Manchester Chamber of Commerce said the issue was not "a parochial north vs south issue", and that "now is exactly the right time to call for Crossrail 2 not wait until Crossrail has opened and reaches capacity".