London now has a population of 8.6m, the highest since the start of World War Two
London's population has topped 8.6m, the highest since its 1939 peak, the Greater London Authority has revealed.
The figures show Hillingdon has had the greatest growth in population, while 44% of the city's people are now of black or ethnic minority origins.
Mayor Boris Johnson said the figure was predicted to reach 11m by 2050.
He added the capital was the "best big city on the planet" but said more financial control was needed to fund key infrastructure, like housing.
The capital already has many green spaces, including Regent's Park, although the mayor wants more
London covers a total area of 1,572 sq km (607 sq m) with a population density of 5,197 Londoners per sq km, making it the largest city in Europe.
Hillingdon as a borough has increased from 159,000 residents in 1939 to 289,000 this year, while Islington has seen the biggest reduction, falling from 343,000 residents in 1939 to 221,000 in 2015.
Prof Michael Batty, from University College London, told BBC London 94.9 the population fell after 1939 in part due to "suburbanisation".
He said: "It went down from about 8m to 6.6m over a period of about 30 years and the main reason was suburbanisation - suburban growth, people getting cars, changing transport and also slum clearance.
"London, of course, was less attractive internationally in terms of migration during those years."
He said much of the population growth in the past 10 years was down to international migration, which could make the population size difficult to predict in the future.
"When you have such a large proportion of growth which relates to international migration, this is really dependent on what is happening in the rest of the world," he said.
