Fleets planning to acquire vehicles in tax bands A and B in order to avoid paying the London Congestion Charge have been advised to delay any such moves until after the mayoral election in May.

In an exclusive interview, the Conservative candidate for the mayor of London, Boris Johnson, who is neck and neck in the running with incumbent, Ken Livingston, told Fleet News that if he his elected on May 1, he will not allow vehicles that produce less than 120g/km of CO2 into the zone for free.

He also confirmed that he will scrap Mr Livingstone’s plans to charge high emitting vehicles – those that produce more than 225g/km - £25 to get into central London.

From his office in County Hall, which during its 1980s heyday was a Labour bastion of anti-Conservative thinking led by Ken Livingstone, Mr Johnson couldn’t resist taking a side swipe at his rival.

“Livingstone has moved the goalposts,” he says referring the mayor’s move from a congestion to an emission charge that targets cars that emit more than 225g/km.

“It is to prove he still has the spirit of Che Guevara running in his blood – he wants to stick two fingers up at the fat cats.”

Although when Mr Johnson launched his transport manifesto, Mr Livingstone called his rival “remarkably dim”, so there is no love lost between the pair.

However, Mr Johnson has a point.

Even Transport for London (TfL) admits that the new £25 charge will reduce emissions by a minimal amount – 2% at best – and, by allowing band A and B vehicles in for free, congestion may actually get worse.

To have such a true-blue Conservative campaigning from the building that was once controlled by the capital’s leftist council, the GLC, and which often had anti-government slogans hanging from the window that Mr Johnson now admires the view of Parliament from, must leave a bitter taste in Mr Livingstone’s mouth.

Boris Johnson knows his transport policy will make or break his election campaign.

He says he has no plans to extend the congestion charge, but neither will he scrap it.

However, he will hold a consultation on the western extension to the congestion zone, which was introduced despite widespread opposition.

He promises that if the majority of residents affected by the extension want it removed, he will abolish it with the zone reverting back to its original size.

“I do want to stop clobbering motorists,” assures Mr Johnson. “I want to make travel by car into London slightly less hellish.”

However, this comes from the mouth of a committed cyclist who wants to see Londoners get back on their bikes.

But the pro-motorist rhetoric continues - he promises to reverse the current TfL strategy of synchronising traffic lights against motorists.

“If traffic is moving it is producing fewer emissions,” he points out in a lucid moment which is a far cry from the mumbling character most would recognise.

“Therefore I will re-phase traffic lights to get traffic flowing more smoothly… Basically I am against cars coming into London, but if they are going to and are willing to pay the charge, then they should have the right to have a smooth journey.”

During the interview, however, one can’t get away from the feeling that Mr Johnson is trying too hard to please, in this case, Fleet News readers.

He is on a mission to get elected and, while the transport policies in his manifesto have been well thought out, his off-the-cuff, buffoonish style perfected on Have I Got News for You, may not serve him as well as he hopes.

One can’t help wondering whether he considers being mayor of London with the same lax attitude he had when he was appointed shadow arts minister.

When asked why he had been appointed he said: “Look, the point is ... err, what is the point? It is a tough job but somebody has got to do it.”

With Ken Livingstone, fleet managers know where they stand – if you have to drive into London then come in a low emission vehicle, and be prepared to have an expensive, slow, disjointed journey.

With Mr Johnson, it is a unmapped road ahead, although there are a lot of encouraging answers for those who must drive into the capital on businesses.

For example, Mr Johnson has committed to making it easier to pay the congestion charge.

Last year almost £95 million was raised in penalty charge notices from those who failed to pay the congestion charge before entering the capital.

“I will move to an account-based system,” he promises.

This means fleets can register with TfL and receive a monthly bill in arrears.

Mr Johnson also wants the mayor to have powers to penalise utility companies that are responsible for poorly run road works.

But, just a month ago transport minister, Rosie Winterton, said she will give councils new powers to penalise utility companies that fail to ensure road works are properly managed and coordinated.

Now Mr Johnson says he should have the same powers.

But still it wouldn’t be the first time teams at opposing ends of the political spectrum have lifted each other’s ideas.

While it is up to those living in the capital to choose their next mayor, their decision will have a dramatic effect on every fleet that needs to enter the capital or even circumvent it.

And the Londoners’ decision will not be easy - they must chose from a committed anti-car socialist who wants vehicles out of London or a true-blue Tory who seems, at present, too eager to please all travellers.

There is another choice – the Liberal Democrat Brian Paddick – who wants to solve London’s chronic transport problems by brining back trams.