Brazil’s president has challenged other world leaders to attend next month’s climate talks in Copenhagen to break the deadlock in negotiations to cut greenhouse gas emissions.

Luiz Inácio Lula da Silva told the Financial Times he would speak to Barack Obama, US president, next week to urge him and other leaders to go to Copenhagen on December 16-17, the final days of the talks, to save them from failure.

“We may not reach an agreement because of a deficiency of global leadership,” Mr Lula da Silva said. “The discussions have been outsourced to advisers but it is better that the ones who say yes or no are prime ministers and presidents.”

Mr Lula da Silva named Hu Jintao, China’s president, and Manmohan Singh, India’s prime minister, as key participants and said he would attend if other leaders did.

He made no new commitments to curb Brazil’s emissions. However, the call from a president with substantial success in the world’s ninth-largest economy, which has grown impressively in recent years, raises the pressure on other leaders to attend.

Todd Stern, the US climate envoy, has suggested Mr Obama will go only if a deal seems close. Gordon Brown, UK prime minister, says he will attend if it helps secure a deal.

In Barcelona on Thursday, at the last round of formal talks before Copenhagen, the UN and leading developed countries raised the prospect of negotiations dragging on to the end of 2010.

Mr Lula da Silva also called on rich countries to promise more money to help poorer countries cut their emissions.