This the story of Three Men in a Bus. They boarded at Downing Street, which seemed a bit odd, not least because the bus was pointing towards a dead end. The bus had no driver, there was no bus stop and the three had no tickets. Since the bus was going nowhere, it probably didn’t matter, but on real buses I have seen people thrown out into moving traffic for less.

I am not sure the three men knew how odd it all was. It’s not the kind of thing you care about if you are the Prime Minister, the Chancellor or the Environment Secretary. After all, this was a political bus that runs on biofuel (when it is actually running, of course). Only carbon dating can tell us the last time any of these three had to fight with a wonky machine to purchase a prepaid bus ticket in order to board without fear.

These men are, arguably, the most powerful trio in Britain. But power doesn’t buy you small talk and, as they sat gingerly on the bus going nowhere, they looked a bit lost. Tony Blair was bemused, for he can always see what he looks like to others (a real political talent). Gordon Brown was chatting fiercely about biofuels, possibly to himself. David “Davy” Miliband just looked as if he was desperate to get off.

As the bus wasn’t moving, this was easy to do. We trooped into Downing Street, where a roomful of teenagers awaited to question them about the Climate Change Bill. The three men sat in front, Gordo at one end, Tony the other. Davy was piggy in the middle. Davy’s head began to swivel from left to right as if he were at a tennis match. I couldn’t help but feel for him.

All three spoke. Tony explained how he was saving the world and that the British people were leading a world revolution. Gordo also is saving the world. He was impressed by the Make Poverty History campaign. He wants to Make Climate Change History, too (expect lime-green wristbands asap). About halfway through, I began to worry about Davy. Surely, with his head in constant motion, he was in serious danger of political whiplash?

Davy then told the kids about the bus. “We’ve just seen a zero carbon bus outside!” The man next to me, who had invented the bus, began to mutter. Apparently, the bus is only 80 per cent carbon free. “It smells a bit of chips, I think, when it runs,” said Davy. More muttering from the man. The bus did not smell of chips (or fish, apparently, which is a shame).

A boy then asked the Prime Minister if he would help him to get solar panels for his school. The PM looked flummoxed. Then, the Chancellor boomed. “There are two things, the Microgeneration Fund and there is also Building Schools for the Future programme.”

For a moment, I saw the future. The Chancellor burbled away about solar panels (they are going be 50 per cent cheaper in a few months, so don’t buy now). Mr Blair could only stand and watch, while Davy sat and swivelled. The political climate is changing, too, before our eyes.

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