In 2009, she had promised to transform Kolkata into London and she did mention that in the Trinamool Congress' 2009 Lok Sabha election manifesto. At the time, she was in the opposition. Her party had stormed to power in West Bengal in 2011 and Mamata Banerjee became Chief Minister of the state.

After more than a decade of her promise, Banerjee on Tuesday introduced two open-roof double-decker buses in Kolkata, much like London's iconic red double-decker buses that have become a national symbol of England.