African leaders set their sights on battling climate change on Tuesday on the final day of a summit hosted by President Nicolas Sarkozy to renew France's ties on the continent.

Sarkozy set the tone for the talks with the 38 African leaders when he warned that developing nations must make good on their promises of billions of dollars in aid to poorer countries at the Copenhagen summit.

"These commitments must be scrupulously kept. Unless we want international conferences to lose all credibility," Sarkozy said at the opening of the summit on Monday in the Mediterranean city of Nice.

At the Copenhagen summit in December, developed countries agreed to provide 30 billion dollars for three years to help poorer nations battle climate change.

Part of the funds are earmarked for battling deforestation in the Congo basin, home to the world's second largest forest after the Amazon of Brazil.

But questions have been raised as to how much of that aid has been raised since Copenhagen and whether it will indeed be new financing, on top of existing development aid.

Ethiopian President Meles Zenawi, who will chair the debate on climate change in Nice, voiced scepticism earlier this month that the financing would ever reach those in need.

Zenawi however warned that the future of UN climate talks hinged on getting firmer commitments, a veiled threat as governments scramble to achieve progress at a key meeting in Cancun, Mexico later this year.

"There will be no legally binding agreement on climate change unless there is a reliable and adequate accord on financing," Zenawi said at an African Union meeting in Addis Ababa earlier this month.

The 25th Africa-France summit is Sarkozy's first since taking office in 2007 and reflects France's shift away from its traditional west African allies toward engagement with the continent as a whole.

About 80 French business leaders including top bosses at oil giant Total and nuclear behemoth Areva are taking part in summit talks along with 150 heads of African companies.

Announcements were expected on Tuesday on a new solar energy project, a social responsibility charter for French businesses and private equity funds for African firms.

The push on the economic front comes as France has taken a back seat to China, Africa's biggest trade partner, which has injected billions over the past decade to tap into raw materials needed to fuel its hungry economy.

At a dinner with African leaders late Monday, Sarkozy declared that the time when Africa's political problems dominated summits was over and that trade and business were now at the forefront.

"Today we can talk about technology, innovation and research with Africa," said Sarkozy.

Private sector investment in Africa has shot up from some 17 billion dollars in 2005 to 88 billion dollars in 2008, said Africa expert Karim Dahou of the Organisation for Economic Cooperation and Development (OECD).

"Aid can be useful if it is used in conjunction with other resources but aid alone will not develop Africa. The private sector has a major role to play," said Dahou.

Declaring that "Africa is our future," Sarkozy has also backed a permanent seat for Africa at the United Nations Security Council among other changes needed to give the continent a greater say in global affairs.

"I am deeply convinced that it is no longer possible to discuss major world issues without the presence of Africa," Sarkozy said.

Among the heavy hitters at the high-level talks are South Africa's President Jacob Zuma, who travelled to Nice just weeks before his country hosts the football World Cup, and Nigeria's new leader Goodluck Jonathan, sworn in this month.