The 16th Summit of the Association of Southeast Asian Nations (ASEAN) opened in Vietnam's capital, Hanoi, today afternoon with all ASEAN leaders attending the opening ceremony at the National Convention Center except Thai Prime Minister Abhisit Vejjajiva. Abhisit has cancelled his scheduled trip to Vietnam due to red- shirted protests in Bangkok. Thai government declared a state of emergency in Bangkok yesterday to control the mass anti-government rallies.The two-day ASEAN Summit is the first high-level event this year as Vietnam holds the bloc's presidency. The summit will focus on measures to enhance solidarity and cooperation within the group, effectively implement the ASEAN Charter and roadmaps for building the ASEAN Community, as well as deepen ASEAN's cooperative ties with partners.At the opening speech, Nguyen Tan Dung, Vietnamese prime minister and chairman of the 16th ASEAN Summit, said ASEAN has entered a new stage of development, steadily moving towards the realization of the ASEAN Community by 2015 and operating on a legal foundation as provided for by the ASEAN Charter. The prime minister said ASEAN must not only strengthen its unity and cooperation, but also overcome its own limitations so as to realize the goal of building an ASEAN Community and maintaining the bloc's centrality.Dung said the most important thing for ASEAN member countries now is to join hands in action, undertake concrete steps and measures to accomplish the set goals and plans.Three important documents, including the ASEAN declaration on sustainable recovery and development and the declaration on responses to climate change and ASEAN Chairman statement will be adopted during the Summit.