'Walk, cycle, and use public transport throughout June and help decongest Britain,' is the message of the Don't Choke Britain campaign.
The campaign, which is coordinated by the Association of Metropolitan Authorities, will be launched on 31 May by transport secretary George Young and health minister Baroness Cumberledge. Events include:
-- 'Car free' days in Bath, Newcastle, Worcester, Winchester and Taunton
-- National Walk to School Week 10-14 June
-- A lobby of parliament, 19 June
-- Green Transport Week, 8-16 June
-- 'Curb the Car' day 30 June
Supporters include celebrities Ben Elton and Spike Milligan.
'It is easier and quicker to get around in the city on foot. You'll find me walking past London traffic jams. I support Don't Choke Britain campaign as someone who is very concerned about air quality in Britain,' said Ben Elton.
AMA public transport committee chair Mark Dowd said: 'Don't Choke Britain is the most wide-ranging transport campaign to help people in Britain to breathe easier.
'The support we are getting shows how many organisation recognise the need to encourage people to cut pollution by using cleaner modes of transport,' cllr Dowd said.