The 16th Summit of the Association of Southeast Asian Nations (ASEAN) opened Thursday afternoon with all ASEAN leaders attending the opening ceremony at the National Convention Center except Thai Prime Minister Abhisit Vejjajiva.

Abhisit has canceled his scheduled trip to Vietnam due to red- shirted protests in Bangkok. Thai government declared a state of emergency in Bangkok Wednesday 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 accelerating the realization of the Roadmap for an ASEAN Community and implementation of the ASEAN Charter; promoting ASEAN connectivity; enhancing cooperation to deal with global challenges affecting the region; strengthening ASEAN's external relations and ASEAN's role; exchanging views on regional and international issues of mutual concern.

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.

"The overall theme for the year 2010-'Towards the ASEAN Community: from Vision to Action'- underlines ASEAN's focus and strong sense of action for this year and beyond," Dung said.

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.

Right before the opening ceremony, the ASEAN leaders tentatively had their first official meeting with representatives of the ASEAN Inter-Parliamentary Assembly (AIPA) cooperation as well as their contribution in the ASEAN Community building process.

Dung called for executive and legislation joint efforts in each ASEAN country to implement ASEAN resolutions and ASEAN Charter.

Dung made the remarks in a meeting between ASEAN leaders and ASEAN Inter-Parliamentary Assembly (AIPA) representatives.

Nguyen Phu Trong, chair of AIPA this year, said AIPA will assist legislative body in each ASEAN country to effectively implement resolutions covering a number of issues.

AIPA will work together with ASEAN to intensify dialogue exchanges and cooperation to help ASEAN member countries deal with multilateral issues, said Trong.

This is the first official meeting between ASEAN leaders and AIPA representatives. At the meeting, participants discussed the promotion of ASEAN-AIPA cooperation as well as AIPA's role in the ASEAN Community building process.

Meanwhile, ASEAN foreign ministers signed here Thursday a protocol on dispute settlement mechanisms within the region.

The signing of the Protocol to the ASEAN Charter on Dispute Settlement Mechanisms signifies the determination of ASEAN in transforming ASEAN into a rule-based organization, said Pham Gia Khiem, Vietnamese Deputy Prime Minister and Foreign Minister at the signing ceremony.

It will help facilitate the implementation of ASEAN Charter and Community building, said Khiem.

Khiem said that the ASEAN foreign ministers are working on finalizing three other dispute-settlement related instruments, including the rules for references to the ASEAN Summit, the procedures for authorization under international law and domestic law, and the rules of procedure for requesting the ASEAN Secretariat to interpret the ASEAN Charter.