A new report by the Corporation of London's city engineer recommends a further pounds 50,000 study be carried out by the City of London and nearby local authorities.
A second river crossing near Tower Bridge is one option expected to follow.
The idea was dismissed in a Department of Transport study last year.
But last autumn, Tower Bridge was forced to close for repairs and Rotherhithe tunnel was temporarily shut this year, prompting the rethink by the corporation's engineers.
Lorries exceeding the Tower Bridge weight limit have also increased concern.