Leaders from the world's eight major industrialized nations meet Wednesday in the German Baltic Sea resort of Heiligendamm for their annual summit, amid tensions between the United States and Russia.
German Chancellor and summit host Angela Merkel has put global warming on the top of the agenda. She has said she will not compromise in getting the other G8 members to cut greenhouse gasses that contribute to global warming.
The G8 leaders also plan to discuss debt relief for Africa. Some experts say the G8 has failed to carry out many of the promises made to Africa at their summit two years ago.
But much of the attention at the talks will likely be focused on disputes between Russia and the United States, including democracy and plans for a U.S. missile defense system in Eastern Europe.
President Bush said in Prague Tuesday that the system is a purely defensive measure and that Russia is not America's enemy.
But he also accused Russia of backsliding on reforms he says once promised to empower Russian citizens.
A spokesman for Russian President Vladimir Putin disputed the Bush accusations, calling Russia a democratic state that shares global values.
Russia also strongly opposes U.S. support for supervised independence for Kosovo -- a majority ethnic Albanian province of Serbia.
Russia, a traditional Serbian ally, says granting independence to Kosovo would violate the territorial integrity of a U.N. member state.
The G8 summit is scheduled to last three days. German police have sealed off the meeting site from the estimated 100,000 protesters who have gathered in the vicinity. The G8 members are Britain, Canada, France, Germany, Italy, Japan, Russia, and the United States. Leaders from China, India, Brazil, Mexico, and a number of African countries will also attend.