Jin Canrong, vice director of the School of International Studies at Renmin University of China, said that ASEAN countries are taking a positive step in making the meeting bigger and more encompassing by inviting the US and Russia, but it may cause ASEAN countries to lose control of the meeting.

Jin speculated that the 10 ASEAN countries are probably concerned with China's rapid rise, and they want to use the US and Russia as counterbal-ances.

The 10-member ASEAN bloc comprises Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam.

Cheng Chongren, a professor with the Institute of International Relations at Fudan University, said that "the US is seeking to gain a foothold in Asia, as well as a member country status in the East Asia Summit, in the context of containing China."

The latest visit to Hanoi marks Clinton's second visit to Vietnam in less than four months. In July, Clinton said, "The United States has a national interest in freedom of navigation, open access to Asia's maritime commons and respect for international law in the South China Sea."

Premier Wen arrived in Hanoi Thursday and is expected to attend meetings with other leaders. The foreign ministers of Japan and China will meet today, boosting chances of talks between Wen and his Japanese counterpart Naoto Kan to calm a diplomatic row, AFP reported.

Sun Zhe, director of the Center for US-China relations at Tsinghua University, noted that disputes between China and ASEAN countries haven't intensified, so he doesn't believe the bloc will be easily used by the US to contain China.

"ASEAN countries are fully aware that only if they maintain a good relationship with China can they develop their own economies," Sun said.