“That Mandelson is trying to make political capital out of climate change just days after reports that he met with BAA’s top lobbyists to push through the third runway is an insult to my generation, We know that Mandelson is best buddies with BAA’s top lobbyist Roland Rudd, and reports suggest it was him who bullied Energy Secretary Ed Miliband into accepting a third runway. We can’t let the Prince of Darkness cast his shadow over West London. The only thing green about Peter Mandelson is the slime coursing through his veins.”

"Democracy has failed us. It's direct action, and direct action historically has been a major way that we have got change. You can look back historically through the suffragettes, through the miner strikes, through all of the major changes. It's about putting yourself in the way."

"Yes this is a silly prank, but it is a silly prank that has allowed us to articulate the reasons why we did it, There are other ways to have your voice heard but they are being pursued by established organisations like the National Trust and they haven't worked. Emissions are still going up and we are careering headlong into the end of the world as we know it. So if today's stunt smacks of desperation, that's because we are desperate."

"It was a grave decision that I had to take to highlight this, but we cannot have people like Peter Mandelson standing by and being applauded for his actions on climate change when he's agreed to the third runway and bullied others into that,"

Plane Stupid, the anti-aviation group, has covered Lord Mandleson, the Business Secretary, with Green Custard. He was on the way to a low-carbon summit when Leila Deen, 29, struck him in the face with the goo. Lord Mandleson dismissed it as an "adolescant" protest.

Rebecca Lush, an environmentalist and anti-roads campaigner, is a serial custard-pier.
She hit Ann Widdecombe, the Tory MP, with an egg and humiliated Alistair Darling, when he was transport secretary, by smearing a carrot cake across his face.

Rebecca says such action is far from immature. “You grab attention through direct action. I don’t think people would have thought about these issues otherwise. Direct action is about making people think, ‘Why is that woman doing that?’ People thought we were weird, in 1992, to risk our lives by standing in front of bulldozers. But environmentalists are always putting out messages that we’re derided for until, 10 to 15 years later, the ideas have become mainstream.”

Here Rebecca explains why direct action works and why she meringued Jeremy Clarkson in 2005.

"When I landed that pie on Jeremy Clarkson’s smug, self-satisfied face I could almost hear the cheers resounding around the country.

"When the text messages and e-mails started arriving they confirmed how much joy I had caused. Just deserts for Clarkson was the theme.

"In fact, it wasn’t any ordinary pie. It was a fair trade organic home-baked banana meringue, chosen because I knew that every politically correct element of it would irritate Motor Mouth all the more.

"His childish and sexist response — calling me “premenstrual” and an “angry bird” — insults that, like him, hark back to the 1970s, show how outdated Clarkson and his values really are.

"What he has discovered is that the environmental movement has a sense of humour too — but a very different one from his. And what has been clear to most of us in that movement is that Clarkson needed bringing down a peg or two.

"The environmental movement has many detractors, and none of us would argue that we should be exempt from criticism, but recently his attacks have gone beyond fair comment and are edging dangerously close to incitement to kill.

"Take, for example, his tasteless comments after the terrorist attacks in London, when thousands of people took to cycling. In comments in The Sun, he said he would run down “for fun” cyclists who cruise through red lights. I dread that one of his fans will one day take him seriously.

"Then there’s his attitude to climate change. In January 2005 he wrote: “Of course, there is no doubt that the world is warming up, but let’s just stop and think for a moment what the consequences might be.

“Switzerland loses its skiing resorts? The beach in Miami is washed away? North Carolina gets knocked over by a hurricane? Anything bothering you yet? . . . It isn’t even worthy of a shrug.”

"Well, it wasn’t North Carolina, it was New Orleans. And if the scientists are right, there could be many more like it.

"Of course, Clarkson has every right to make an idiot of himself in the media, and he does it with panache. The problem is the opposite point of view gets heard much less often.

"Let me explain why we should care about climate change. Jeremy is right to point out that other people will be affected by it before we will: it threatens to throw the world into food deficit by 2030, creating a humanitarian disaster in Africa and south Asia. Anything bothering you yet?

"When I became an eco-activist at Twyford Down in the first days of the anti-roads movement in 1992, I was motivated by my fear about climate change. We were 10 years ahead of our time. At last climate change is recognised in the words of Tony Blair as the “most serious threat to mankind”.

"Clarkson was rewarded by Oxford Brookes for services to engineering. In his view, engineering and environment are opposites. But climate change can be tackled only with the help of better engineering and new technologies. Everyone seems to have twigged this, except Jeremy and Oxford Brookes.

"Clarkson’s pie was awarded for services to public ignorance. Next on my list? Well, I’m still baking.