 A summit of major powers in Germany will not agree to any firm targets for slashing greenhouse gas emissions, a senior US official said on Wednesday as G8 leaders gathered on the Baltic coast. German Chancellor Angela Merkel, chairing the annual meeting of the Group of Eight (G8), had hoped to secure US backing for a pledge to halve emissions by 2050 and limit warming of global temperatures to a key scientific threshold of 2 degrees Celsius. But she is now likely to settle for an expression of US support for United Nations efforts to combat climate change and an agreement to tackle emissions at a later date. "We have opposed the 2 degree temperature target, we are not alone in that -- Japan, Russia, Canada and most other countries that I have spoken with do not support that as an objective for a variety of reasons," James Connaughton, a senior climate adviser to US President George W Bush, told reporters. "At this moment in time on that one particular issue we do not yet have agreement," he added, referring to firm targets for cutting emissions that scientists say will swell sea levels and cause droughts and floods. Separately, French Environment Minister Alain Juppe said G8 powers -- Britain, Canada, France, Germany, Italy, Japan, Russia and the United States -- were far from a final climate deal despite months of negotiations. "We are far from a deal because Germany, supported by France, wants to go further, to lay the groundwork for post-Kyoto and to agree quantifiable targets," Juppe told French television. Europeans are still hoping the summit can send a signal about leaders' desire to come up with a successor to the Kyoto Protocol, the global climate deal which runs until 2012 and which the US is not a part of. Merkel was expected to press Bush on the climate issue when she lunches with him on Wednesday. She will later meet with Russia's Vladimir Putin before holding a dinner and reception for all the G8 leaders in Heiligendamm, a seaside resort founded in 1793 as an exclusive summer spa for European nobility. On the eve of the meeting, Bush criticised Russia on democracy, escalating a war of words with Putin that Merkel fears could overshadow other key themes like climate change and aid for Africa. "In Russia reforms that once promised to empower citizens have been derailed, with troubling implications for democratic development," Bush said during a visit to Prague on Tuesday. Differences between Washington and Russia centre on US plans to deploy parts of a missile shield in Poland and the Czech Republic. Moscow is also resisting a push by Washington and European countries to grant independence to the breakaway Serbian province Kosovo. Leaders from the G8 are expected to discuss other foreign policy issues including Iran's nuclear programme, Sudan and the Israel-Palestinian conflict. The world's top industrial powers first gathered in 1975 in Rambouillet, France, to coordinate economic policy following a global oil crisis and the collapse of the Bretton Woods system of fixed exchange rates. Recently, the club has come under pressure to adapt to shifts in global economic power. Merkel has invited leaders from Brazil, China, India, Mexico and South Africa to address those concerns. A number of African leaders have also been invited for an "outreach" session on Friday. It was unclear on the eve of the summit whether G8 countries would make ambitious pledges on development aid and AIDS funding for Africa. Some 16,000 security personnel are in the area for the summit. The leaders will be shielded from thousands of demonstrators by a 12-km (7.5-mile) fence topped with barbed wire. Almost 1,000 people were injured on Saturday when violence broke out at an anti-G8 protest in the nearby city of Rostock.