Mr Livingstone promises more police units if he is re-elected

Since launching the congestion charge, Mr Livingstone is now pushing for greater restrictions on heavy traffic.

He said high polluting buses, lorries and cabs would be banned from the centre of London by 2007.

Mr Livingstone will take on Tory Steve Norris, Liberal Democrat Simon Hughes and other candidates on 10 June.

Speaking to BBC London, Mr Livingstone said a ban would make a "real impact" on London's air quality.

LIVINGSTONE'S MANIFESTO Introduce low emission zone More local police teams Improved bus services 30,000 new homes Affordable childcare Later weekend Tube services Free bus travel for under-18s

"The government has given me the power and has now guaranteed the money to have a low emission zone in London," he said.

Unveiling his full manifesto in Sutton, south London, Mr Livingstone said he would continue to develop the policies introduced during his four years in office.

Improved public transport and increases in neighbourhood police numbers are at the top of the 44 page agenda.

The manifesto pledges to extend the neighbourhood police unit programme which puts small dedicated teams of officers on the beat in local areas.

And travellers can expect more new buses and a later service on the Underground on Friday and Saturday nights.

Low cost housing is also promised by Mr Livingstone who has set a target of 30,000 new homes year with at least half of them to be "affordable".