COP21: If we don’t strike climate deal in Paris it will be too late, says Barack Obama

Failure to reach an agreement would make it virtually impossible to avoid devastating climate change

President Obama has said that when it comes to climate change, there is such a thing as being too late (Reuters)

World leaders have urged negotiators – and each other – not to throw away a unique opportunity to agree decisive action to curb climate change, as talks at the United Nations summit begin in Paris.

Nearly 150 leaders and heads of state, including David Cameron, Barack Obama and Prince Charles, were at the opening of the make-or-break conference to tackle global warming.

The US President invoked the urgency of the civil rights movement in his homeland 50 years ago. “I believe in the words of Dr Martin Luther King Jr that there is such a thing as being too late,” said Mr Obama. “And when it comes to climate change, that hour is almost upon us.”

He added: “What greater rejection of those who would tear down our world than marshalling our best efforts to save it? We salute the people of Paris for insisting that this crucial conference will go on.”

David Cameron talks to Francois Hollande as Prince Charles looks on in Paris (Reuters)

Prince Charles echoed his call, urging world leaders to “think of your grandchildren, as I think of mine”, as he demanded greater action to tackle climate change.

During the two-week conference, representatives from nearly 200 countries will work furiously in the hope of agreeing a treaty strong enough to limit global warming to 2C, beyond which the consequences become increasingly devastating. In the run-up to the summit,

more than 170 countries have pledged to cut carbon emissions that would limit climate change to 2.7C. They must now agree a way to ensure those pledges are monitored and met and a system that would require each country to increase its pledge every few years until the 2C target is hit.

The presidents of Russia and the US were among leaders discussing climate change (PA)

Failure to reach an agreement would make it virtually impossible to avoid devastating climate change, as it would take years to rebuild sufficient momentum to make another attempt. “You are here today to write the script for a new future… A political moment may not come again. We have never faced such a test. But neither have we encountered such great opportunity,” said the French President François Hollande.

The UN climate chief, Christiana Figueres, added: “The eyes of millions of people around the world are on the Paris meeting. You have the opportunity, in fact the responsibility, to finalise an agreement that delivers.”

But leaders were at pains to remind each other that a huge amount of work remains to be done and in a short period.

In his speech, David Cameron asked how we could possibly explain to future generations that we had the opportunity to tackle climate change but didn’t take it.

“Let us imagine what we’d have to say to our grandchildren if we failed. We’d have to say that it was all too difficult and they would reply what was so difficult when the world was in peril?” he said.

“What we are looking at is not too difficult. It is doable and therefore we should come together and do it,” Mr Cameron added.

But campaigners accused the Prime Minister of preaching one thing while practising another at home in the UK.

David Cameron’s grandstanding on the international stage is riven with hypocrisy because of the complete incompetence of his government on climate change at home. Since the election. the UK government has taken a wrecking ball to clean energy and low carbon policies,” said Friends of the Earth chief executive Craig Bennett.