London's population density could soon match Rio's

London could match the population density of Rio de Janeiro or Bangkok unless the city begins development outside its boundaries, a cross-party report warned.

The London Assembly's Planning Committee set out options for future development in a report written for whoever wins May's mayoral election. It said London, which last year exceeded its 1939 peak population of 8.6 million, is on course to expand to 10 million people by 2031.

To accommodate this growth, the city needs to build at least an extra 49,000 homes a year and only has the capacity to build an extra 42,000 a year. The committee declined to offer recommendations.
 
London currently has 5,206 people per square kilometre, Rio has 6,850 and Bangkok has 6,450. Paris only has 3,350 people per square kilometre.