Bush thanked Nazarbaev for supporting the U.S.-led war in Iraq and for helping Afghanistan to become more stable and democratic.
"Neither Kazakhstan nor anyone else in Central Asia would feel safe and at peace if we were surrounded by countries populated with terrorists and if we were surrounded by countries that want to get weapons of mass destruction, which Kazakhstan voluntarily renounced in the past and, thus, contributed significantly to global security," Nazarbaev said in response.
The U.S. president offered support for Kazakhstan's bid to join the World Trade Organization.
Nazarbaev expressed gratitude for U.S. support for Kazakhstan's independence from the Soviet Union 15 years ago and lauded Kazakhstan's economic development.
"Kazakhstan today is very proud that we have the highest rate of economic growth in the world, and the life of our people is improving every year. A lot of countries learn from the experience of Kazakhstan today," Nazarbaev said.
Kazakhstan is a major oil producer.
Rights groups have criticized the country's human rights record. Prior to the meeting, the New York-based Freedom House and other groups that support democracy and protection of human rights had called on Bush to make the issue a priority of the summit.