Detailed plans for an east London river crossing have been unveiled as part of a public consultation.
Residents are being asked their views on the proposed Silvertown Tunnel, which would connect the Greenwich Peninsula with the Royal Docks.
Transport for London (TfL) said it hoped the tunnel beneath the Thames, which will cost an estimated £750m, would reduce congestion.
But the No to Silvertown group said it would "increase air pollution".
The London mayor Boris Johnson said the crossing would be a "vital new link".
'Growth potential'
"The Silvertown Tunnel would provide a vital new link beneath the Thames from two of our city's great opportunity areas for new homes and jobs - Greenwich Peninsula and the Royal Docks," said Mr Johnson.
"Unless new river crossings are provided, the huge growth potential of east London will not be realised."
The consultation includes proposals to charge users of the Silvertown and Blackwall Tunnels to help fund the construction of the new crossing, however the charges would be introduced after the tunnel opened.
