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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London singer-songwriter Dua Lipa and Croydon grime artist Stormzy led the charge at the Brit Awards, winning two prizes each.
The awards followed the lead set at the Grammys to show support for the Time's Up movement with artists wearing white roses.
The husband of a British citizen jailed in Iran has delivered letters of support for his wife to the Iranian embassy.