LONDON: Britain's Gordon Brown heads to China and India Thursday for his first visit as prime minister, looking notably to get the world's two most populous countries on board for a new deal on climate change.

Brown, who visited both countries as finance minister in his predecessor Tony Blair's administration, has said he wants to press Beijing and New Delhi to sign up to a post-Kyoto Protocol deal from 2012.

"I believe that gradually all developing countries, all emerging market countries as well as America and Europe will want to be involved in an agreement that will be a binding agreement for the future," he said last month.

Brown has said he also wants to discuss the state of the world's economy with his counterparts Wen Jiabao and Manmohan Singh, amid fears of a recession in the United States and a global downturn.

In China -- where he visits first -- the Olympics, which Beijing hosts in August and come to London in 2012, and boosting two-way trade and investment and links in science, technology and education are also likely to feature.

European leaders are courting the emerging economic giants: on a visit to China last November, French President Nicolas Sarkozy announced some 30 billion US dollars of deals in the aviation and nuclear power sectors.

The Chinese foreign ministry said Tuesday they attach "great importance" to the visit and will inject "new vitality" into Sino-British relations, which have been steadily improving in recent years, and boost world stability.

But environmental groups questioned whether Britain -- which aims to become the world's first low-carbon economy with legally-binding targets on emissions cuts -- is best-placed to push China and India on "green" issues.

Government backing for new nuclear plants, its support for growth in the aviation sector and approval for Britain's first coal-fired station in 24 years stood at odds with its tough talk on combating global warming, they told AFP.

Doubts have also been raised about whether Britain can meet a European Union target to cut emissions by 20 per cent of 1990 levels by 2020 while the level of investment in renewable energy sources like wind power has been criticised.

The US environmental research group Worldwatch said this month that China is poised to become the world leader in renewables, as it seeks to wean itself off coal as its main source of energy.

Friends of the Earth International's climate and energy co-ordinator Joseph Zacune said Britain and the developed world need to "put their own house in order" first.

"Britain and other developed countries need to commit to binding targets first and lead the way for developing countries such as China and India to follow," he said.

Greenpeace's senior climate adviser Charlie Kronick told AFP Brown was likely to face questions about financing for developing clean technology and evidence of Britain's progress on the issue.

Britain is currently helping on a carbon capture storage scheme in China and is working on a joint research project with India to assess the impact of climate change on the sub-continent.

But Kronick said: "It's very, very difficult for us to have any leverage until we start to make some really pretty significant changes here in the way that we deal with climate change and energy."

Developed nations, including Britain, should place more emphasis on and pledge investment in helping developing countries adapt to climate change, mitigating its effects and creating cleaner technology, both analysts said.

Representatives of China and India, which both class themselves among developing nations, argued along similar lines at the United Nations climate change conference on Bali last December. - AFP/ac