London's mayoral race under way
Nominations are opening for the London mayoral election, with Labour's Ken Livingstone facing his biggest challenge since taking office in 2000.
He is competing with Conservative Boris Johnson and Lib Dem Brian Paddick, with about ten others expected to stand.
Mr Livingstone launches his bid for a third term at the Royal Festival Hall, while Mr Johnson is visiting Tooting.
A poll for the Evening Standard suggested Mr Johnson had 49%, Mr Livingstone 37% and Mr Paddick 12%.
Other candidates polled 3% in the YouGov poll.
The mayoral election and London Assembly elections take place on 1 May, with nominations due to close on 28 March.
Thirteen candidates have said they will stand for the top job.