London could have the world's first Ultra Low Emission Zone

In a bid to improve air quality, mayor of London, Boris Johnson, has announced that London could have the world's first Ultra Low Emission Zone.

As London is among the worst in Europe for air pollution, the mayor has made it his priority to sort out the problem.

However, Mr Johnson will only be mayor until 2016, so he is attempting to set the precedence for the future mayor by outlining the terms of the new zone now.

His plans consist of allowing only zero and low-emission vehicles in the central London zone by 2020.

Although the timeframe has been called ambitious, environmental organisation ClientEarth has warned that in terms of European Union rules, London will have "illegal levels of air pollution until 2025".

In addition, a report last December found that nine per cent of deaths in the city were down to air pollution.

Although some have called the timescale ambitious, others have said it is not soon enough.

Indeed, Simon Birkett from Clean Air In London said the timescale was far too long and that it would only cover the central Congestion Zone.

"It's the biggest public health risk after smoking and we need bold action - he should have been starting on this in 2008 need bold action in two or three years, not seven or eight," he said.

In a speech to City Hall, Mr Johnson said: "Creating the world's first big city ultra low emission zone has the potential to be a game changing moment in the quality of life of our great capital.

"My vision is a central zone where almost all the vehicles running during working hours are either zero or low emission.

"This would deliver incredible benefits in air quality and stimulate the delivery and mass use of low emission technology."