Rio Earth Summit postponed after clash with Queen’s diamond jubilee

Brazil has postponed the biggest environmental summit in 20 years to avoid a clash with the Queen’s diamond jubilee.

The Rio+20 summit was scheduled for 4-6 June but has been moved to 20-22 June to avoid jeopardising the attendance of 54 Commonwealth leaders, including David Cameron. But Cameron, who said last month that he would not attend, is still not planning to attend, Downing Street said on Monday, despite his pledge to lead the “greenest government ever”.

Instead, the environment secretary, Caroline Spelman, will be leading the negotiations, a Downing Street spokesman said.

Though Brazil has not officially confirmed the date change, president Dilma Rousseff indicated at the G20 meeting in Cannes on Friday that the summit would be postponed. Asian governments also asked for the new date following the next G20 summit which is to be held 18-19 June in Mexico. The Guardian understands European governments are already working to the new dates.

Rio+20 will mark 20 years since the original Rio Earth Summit of 1992 and is seen as a chance to renew political commitment for sustainable development and greening the economy. A report by MPs last month called on Cameron to “lead by example” and attend the summit.

Green groups and Labour accused Cameron of failing to show leadership.

Caroline Flint, shadow secretary of state for energy and climate change said: “What a sad turn of events that David Cameron, who would hug a huskie for a press stunt just a few years, has now cold-shouldered the biggest environmental conference for 20 years. Cameron has already shown he is out of touch with the public on energy prices; out of touch on tackling abuse and power of the energy giants; and out of touch on investing in green jobs and growth. Now he is determined to avoid any leadership at all on tackling climate change.”

Margaret Ounsley, head of public affairs at WWF-UK, said: “Now it has been confirmed that the Earth summit is being moved specifically to accommodate the Commonwealth heads of government we would hope that the prime minister can find time in his busy schedule to attend the Rio summit. Managing the Earth’s resources in a way that ensures that there is something left for future generations is still one of the greatest challenges facing humanity. It would begin to sound like he was making excuses if he were still unable to go.” The then prime minister John Major attended the original Rio summit in 1992, despite IRA bombings in London, WWF have noted.

Joan Walley, chairwoman of the environmental audit committee, said: “The Rio+20 Earth summit is a vital chance for world leaders to take action to avert a global environmental crisis. But the financial situation means that minds will be focused elsewhere and there is a danger that business-as-usual may end up carrying the day. The prime minister should lead by example. He could make a big difference by demonstrating his commitment to Rio+20 and letting other world leaders know that he will personally be attending.”