London mayor Boris Johnson has pledged to increase the amount of green space in the capital to keep it cool during summer as part of a series of climate change measures.

The city's climate change strategy also proposes designing or adapting buildings to limit demand for cooling, for example by increasing the number of rooftop gardens to soak up rainwater.

The strategy scrutinises London's ageing flood defence infrastructure and poor drainage network, which was designed to cope with less intense rainfall. Measures to promote energy efficiency and renewables are also suggested to help meet London's target for a 60 per cent cut in carbon emissions by 2025.

Johnson said: "We need to concentrate efforts to slash emissions and become more efficient in order to prevent dangerous climate change."

A range of organisations will now be consulted on the strategy, including the London Assembly, the London Development Agency, the London Fire and Emergency Planning Authority, the Metropolitan Police Authority and Transport for London. A second version will be published for public consultation next year.