Mr Prescott sparked an small outcry when he and his wife, Pauline, travelled the short distance from their hotel to the conference centre by limousine on Wednesday.

Once inside the hall, Mr Prescott used his keynote speech to urge motorists again to help cut pollution by leaving their cars at home in favour of public transport.

But on Thursday Mr Prescott, accompanied Home Secretary Jack Straw - who lists walking among his recreations - to the conference centre on foot.

Mr Prescott said: "These shoes are made for walking."

Asked why he had left his car at the hotel, he said: "I've walked every day except that one day, and I've been having some talks with Jack."

Clare Short: Left her car at home

The deputy prime minister has denied accusations of hypocrisy from Conservatives, environmentalists, motorists and many newspapers.

His cabinet colleague International Development Secretary Clare Short also joined in the criticism.

When asked about the row on BBC2's Conference Live programme, she said: "It's hard. Poor old John. But you know, if you say we must use our cars less, you should use them less.''

She pointed out that she had not brought her car to the conference, adding: "To tell you the truth, I don't like having a car. It means you never walk along the street, you don't see what's in the shops, you get unfit ... so I think getting addicted to having a car is not as good as it sounds.''

Pauline Prescott and hairdo: Safe from sea breezes

Earlier, Mr Prescott - nicknamed "two Jags" - sought to laugh off the criticism.

Asked why he had taken the car rather than walk, Mr Prescott said: "Because of the security reasons for one thing and, second, my wife doesn't like to have her hair blown about. Have you got another silly question?"

A Labour Party spokesman added that Mr Prescott and Prime Minister Tony Blair travelled between the hotel and conference centre by car for security reasons on police advice.

He said Mr Blair made the journey once on foot on Monday as part of a pre-arranged photocall for TV cameras - a move which required extra security.

'Labour's hypocrisy knows no bounds'

But shadow environment, transport and regions secretary John Redwood rejected this explanation.

Mr Prescott has often ditched his car for a photo opportunity

"Labour's hypocrisy knows no bounds - they say one thing and do another, all from the government that tells us to go by bus or train or walk," he said.

Mark McArthur-Christie, traffic spokesman for the Association of British Drivers, said Mr Prescott's behaviour was "incredible".

He also urged the government to put more investment into transport so that drivers would have a genuine choice between using their car or good quality rail and bus services.

Mark McArthur Christie "We think it's incredible that John Prescott should've done this"

"We have challenged him to do what he tells the rest of us to do and hang up his Jaguar keys up and use public transport for a month," he said.

Ian Willmore, spokesman for Friends of the Earth, said: "Politicians need to learn that if they preach the virtues of not using the car, people will notice if they travel 300 yards in a large limousine.