Today is the day the prime minister is supposed to deliver his first major speech on the environment since he came into office two years ago, pledging almost immediately to lead the "greenest government ever". Fittingly, the setting is the Clean Energy Ministerial in London, where Ministers from 23 of the world's leading economies have gathered eagerly to hear it.
But on Tuesday a flurry of tweets emanating from Westminster cast doubt on whether or not the big speech would actually happen. Eventually the Department of Energy and Climate Change confirmed it would not - apparently, Mr Cameron has too many big speeches to do, and so this one will have to kick the bucket.
What we're left with is a five minute Q&A session and a 'press release on the side' - a far cry from the keynote talk we've been waiting for, and what the government itself was trailing. It's been four long years since we heard Cameron speak convincingly about how he wouldn't let financial pressures divert him from showing leadership on the environment. Whatever happened to "Vote Blue, Go Green?" David? What happened to the Conservatives' big green credentials? It's as if he just can't be bothered.
In the face of George Osborne's irrational anti-green rhetoric - reinforced by some right-wing media - the prime minister's silence is even more unsettling. Not just for Ministers at the clean energy summit but for businesses too, who are wondering if Cameron's commitment is genuine. In the week Britain entered a double-dip recession, investors are seeking certainty that renewable energy has the government's long-term backing. It's a vacuum that only David Cameron can fill - and the Clean Energy Ministerial would have been the perfect opportunity to do it.
After all, renewable energy is what the majority of people want. A new YouGov poll for Friends of the Earth reveals that 85% of the public back the introduction of government legislation to get the energy companies off gas and investing in clean British energy from our wind, sun and sea. Asked where they want their electricity to be sourced from 10 years from now, 64% of respondents chose renewable energy - just 2% - want more gas.
Why then, are ministers allowing an unnecessary dash for gas that could lead to twice as many new gas-fired power stations being built as the government itself says are needed? It keeps Britain ever more dependent on increasingly imported gas, which Ofgem says is the main driver behind our escalating fuel bills. Meanwhile, DECC has signalled a green light to risky shale gas fracking - which could be even more polluting than coal, and won't do anything to help us meet our legally-binding targets to cut climate changing emissions.
Our own research shows that, alongside with measures to cut energy waste, developing renewable energy is our best hope of affordable fuel bills in the future. Britain has some of the best wind and tidal resources in Europe - it's time we used the clean energy at our fingertips, and boosted our own economy by exporting our expertise.
David Cameron should be telling the Clean Energy Ministerial exactly that - and of his intention to lead by example by up-scaling investment in the sector. New figures from the Renewable Energy Association show the UK's clean energy sector grew by 11% in 2009-2010 - outstripping investment in fossil fuels. It's one of the only sectors of the economy that's growing and creating jobs right now.
In a few month's time the government has a once-in-a-generation chance to fix our broken power market, and deliver a framework that will drive a shift from dirty and costly imported fuels of the past and unlocks the potential of the clean British energy of the future. The sooner the government focuses on this immense prize, the sooner we tackle fuel bills and secure our electricity supplies going forward.
Next time you need help writing your speeches Mr Cameron, give Friends of the Earth a call.
For more information and to back Friends of the Earth's Clean British Energy campaign, see www.cleanbritishenergy.co.uk.