“Prime Minister Brown, we cannot avert our eyes from the basic fossil fuel facts, or the consequences for life on our planet of ignoring these fossil fuel facts. If we continue to build coal-fired power plants without carbon capture, we will lock in future climate disasters associated with passing climate tipping points. We must solve the coal problem now.” That was Professor Hansen, a director of NASA and one of the world’s most eminent climate scientists, in a letter to Downing Street in December. His call was echoed by the Royal Society in April after Business Minister, John Hutton, ignored climate science and gave his personal backing for new unabated coal, historically the single biggest fossil-fuel source of CO2, in a speech to the Adam Smith Institute. No credible climate scientist now thinks that continuing to burn coal unabated is compatible with tackling climate change. It’s obvious the government needs to accept that new coal plants like the one proposed at Kingsnorth are not an option.

My organisation Greenpeace – together with WWF, Friends of the Earth and the RSPB – last week backed the introduction of tough new greenhouse gas emission performance standards for power stations, like those already introduced in California by arch-hippy Governor Schwarzenegger. These would rule out unabated coal and incentivise clean, renewable technologies to secure Britain’s energy needs. The Cameroonian think-tank, Policy Exchange, endorsed the idea and today the Conservatives announced that they agree with the principle of new standards too.

Whilst the grassroots climate activists who hijacked the train carrying thousands of tonnes of coal to Drax power plant this morning may disagree with the detail of Cameron’s announcement next Monday, it’s clear the rules of the game have changed when the environmental direct action movement and the Tories are united in saying that something needs to be done about coal – and for the same reasons. Equally, I’m sure the climate campers in Yorkshire this morning would agree with the conclusions of the cross-parliamentary Environmental Audit Committee who last week branded Energy Minister Malcolm Wicks “reckless” over his support for new unabated coal burning at Kingsnorth. The more polite ones, anyway.

Apart from the DUP, who remain open to persuasion, the Prime Minister is looking increasingly short of allies on this issue. A consensus is emerging between the Conservatives and Lib Dems, climate scientists, environment and development NGOs, and the grassroots movement. Even the state of Kansas, whose adherence to scientific orthodoxy doesn’t always extend to embracing evolution, has ruled out new coal on climate grounds. Britain’s claim to international leadership on climate change is starting to look a bit implausible.

As old power stations come to the end of the line, the Prime Minister is being offered a unique opportunity. Introducing green standards for power stations would get backing across the political spectrum and make Brown a genuine leader on clean energy.