Aerials show central London gridlocked by black cab demo
11 June 2014 Last updated at 15:06 BST
A protest against a mobile phone app by London's taxi drivers has brought large parts of the centre of the capital to a standstill.
Aerial footage shows the gridlock caused by black cab drivers unhappy at rival Uber, which they claim is not regulated well enough.
Jane Hill and Daniel Boettcher report.