Officials from the two cities received the accolade at a glittering awards ceremony in Washington DC recognising their efforts to cut traffic pollution, fight climate change and create high quality public spaces.

The cities edged out the other shortlisted candidates, Guatemala City, in Guatemala, Eugene, in Oregon, and Pereira, in Columbia, to take the top honours at the awards, organised by the Institute for Transportation and Development Policy (ITDP).

“All of these cities took politically risky decisions that made a huge contribution to reducing greenhouse gas emissions and making their cities more liveable,” said Dr Walter Hook, executive director of the ITDP.

“With their success, dozens of mayors around the world are now finding the courage to take similar steps.”

London is the largest city to adopt congestion pricing, which has inspired other cities such as New York to consider introducing it.

Prior to the charge, London drivers spent 50% of their time in traffic jams, but by 2007 congestion had dropped 21%, carbon dioxide emissions had fallen by 16%, and bus use had risen by 45%.

London mayor Ken Livingstone welcomed the award but said he still had more improvements planned.

He said: “We have no intention of resting on our laurels. We will be making the whole of Greater London a Clean Air – Low Emission Zone from February 4, effectively banning the most polluting lorries from our roads.”

Paris has revolutionised bike-sharing programmes with its Vélib or Freedom Bikes system allowing people to rent bikes for a low fee and return them to any bike parking station across the city.

City authorities are also renovating public squares and plazas and widening sidewalks to encourage pedestrian traffic, building more bike lines and opening lanes for a new bus rapid transit system.

The award selection committee included experts from organisations such as the ITDP, Environmental Defense, the Clean Air Initiatives for Asia, Latin America and Africa, and the United Nations Centre for Regional Development.

Kate Martin

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