George Osborne today gave his financial backing to proposals to build two new River Thames crossings to Silvertown and Beckton.

In his Budget, the Chancellor pledged to work with fellow Conservative and current London Mayor Boris Johnson to invest in public transport and a new Royal Docks enterprise zone.

Transport for London (TfL) consulted on proposals earlier this year for a road tunnel from the Greenwich Peninsula to Silvertown and a new ferry crossing to Gallions Reach.

They will be completed by 2021 provided planning permission is granted and funding is secured.

Speaking in the House of Commons, Mr Osborne said: “We will work with him [Mr Johnson] on plans this summer to go on investing in London transport, lengthening commuter trains, extending the Underground and exploring new river crossings in east London.

Of the planned Royal Docks business zone, he added: “So from the allocation made to the Mayor through the Growing Places Fund he will be creating a new �70m development fund to attract new business and new jobs.”

But Ken Livingstone’s campaign pointed out there was no firm promise of funding for the river crossings or any new investment in London’s rail network, despite it being mentioned in the Budget speech.

Mr Livingstone said: “When it comes to the big issues that affect millions of people in London, Tory Boris Johnson has failed to stand up for Londoners time and time again.”