Chinese President Hu Jintao left Beijing Sunday afternoon to attend the second Nuclear Security Summit in Seoul, the fourth BRICS Summit in New Delhi, and pay a state visit to Cambodia.

The Seoul Nuclear Security Summit, getting together leaders from 53 countries and some international organizations, is scheduled to be held from March 26 to 27. Hu will attend the summit at the invitation of President of the Republic of Korea (ROK) Lee Myung-bak.

While attending the summit, Hu will make an important speech and elaborate on China's position, efforts made and important measures taken in the field of nuclear security, said Assistant Foreign Minister Ma Zhaoxu.

After the Seoul trip, Hu will attend the fourth BRICS Summit from March 28 to 29 at the invitation of Indian Prime Minister Manmohan Singh. The BRICS consists Brazil, Russia, India, China and South Africa. They are also the main emerging economies in the world.

Ma said the president will elaborate on China's position on global governance, sustainable development, and cooperation among BRICS countries at the summit, which features the theme of BRICS countries' commitment to the partnership of stability, security and prosperity.

Hu will also pay a state visit to Cambodia from March 30 to April 2 at the invitation of King of Cambodia Norodom Sihamoni.

China believes that Hu's visit will deepen relations between the two countries and promote cooperation between China and the Association of Southeast Asian Nations, according to the Foreign Ministry.