Mayor of London Boris Johnson today said a new bridge will be built across the Thames at Dartford.

During an #AskBoris question and answer session on Twitter, Mr Johnson replied to query from Mark Bailey, which asked: "When will there be another tunnel/bridge built to ease traffic at Dartford and Blackwall tunnels".

His reply was: "Yes the new silvertown crossing will be in by 2020 followed by 3 more bridges inc Dartford 2."

A number of people criticised the news, with Derek Murray saying: "Dartford 2"? The Thames need more crossings. Dartford most certainly doesn't."  

Elaine Willis added: "and we will pay for ever like the Dartford one despite all the promises!"

In October a think tank called for four new Thames crossings to be built at Silvertown, Gallions Reach, Belvedere and Dartford.

The Linking London report from the Centre for London claimed the new infrastructure is needed to "support a wave of new development travelling eastwards along the Thames".

It called for the development of a new crossing near the current QEII Bridge at Dartford to be "brought forward as soon as possible".

A spokesman for the Mayor of London said: "There is a pressing need for more river crossings in east London.

"As well as the Garden Bridge and the Emirates Airline, the Mayor is proposing options including a new tunnel at Silvertown, which could open by 2022, and new bridges at Gallions Reach and Belvedere.

"He has also supported the Government’s idea of a Lower Thames Crossing east of Dartford and recently referred to potential sites that are currently under consideration by the Department for Transport.

"No decision has been made yet on where it will be located and this decision will be ultimately be one made by Government."