Chinese President Hu Jintao is in London for the Group of 20 (G20) summit, ahead of which he successively met with his US, British, Russian and French counterparts. The following are some facts and figures about his tour.

-- The G20 was initiated at a meeting of G7 finance ministers in Washington, D.C., in September 1999 when the Asian financial crisis had wakened the world's economic powers to the need of incorporating key industrial and emerging market countries into the global economic and financial policy making.

-- The G20 has a membership comprising 19 countries and a regional bloc, including the G7 nations -- the United States, Japan, Germany, France, Britain, Italy and Canada -- and Russia, China, Argentina, Australia, Brazil, India, Indonesia, Mexico, Saudi Arabia, South Africa, South Korea, Turkey and the European Union.

-- The G20 economies account for more than 80 percent of the global gross national product, about 80 percent of world trade and about two thirds of the world population.

-- The objective of the London Summit is to bring the world's biggest economies together to help restore global economic growth through enhanced international coordination.

-- Chinese president Hu Jintao and his US counterpart Barack Obama held their first meeting in London Wednesday on the sidelines of the G20 summit since Obama took office in January this year.

-- China and the United State issued a joint communique On December 16, 1978, and formally established diplomatic relations at ambassadorial level on January 1, 1979.

-- The three Sino-US joint communiques, namely, the Shanghai Communique, the Joint Communique on the Establishment of Diplomatic Relations between the People's Republic of China and the United States of America, and the Sino-US Joint Communique on the US arms sales to Taiwan, have set up guiding principles for the development of Sino-US relations.