Southwark Council leader Peter John has launched a petition calling on the Mayor of London to include an extension of the Bakerloo line south of Elephant & Castle in his next 10-year transport plan for London.
The online petition urges Boris Johnson to commit to extending the line to Camberwell and Peckham.
The council's Labour and Liberal Democrat groups confirmed their backing for the extension last year.
On Wednesday Cllr Fiona Colley, Southwark's cabinet member for regeneration, told council assembly that the borough's Labour administration is "actively pursuing" an extension of the Bakerloo line and that – together with Cllr John and transport supremo Cllr Barrie Hargrove – she had raised the matter in a meeting with Isabel Dedring, London's deputy mayor for transport, earlier this week.
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