Chancellor George Osborne and London Mayor Boris Johnson were at a former gasworks which has been deserted for 40 years to launch the scheme. They say the site in Tottenham can now be built on after they removed planning restrictions to get more homes built quickly.
Fifty thousand new homes will be built, 40% of which will be affordable, housing 250,000 people.
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Chris Gard and Connie Yates want permission to take son Charlie to America for a therapy trial.
Just in time for World Turtle Day too.
London mayor Sadiq Khan said the capital "stands united with the great city of Manchester today after this barbaric and sickening attack".