It is estimated that initiatives ASEAN is implementing under AEC will raise the group's overall GDP by 7 percent by 2025.

The talks on the Regional Comprehensive Economic Partnership (RCEP) which involve 10 ASEAN members and six dialogue partners - China, Japan, South Korea, Australia, New Zealand and India - also topped the agenda at ASEN summit and related meeting.

The RCEP could potentially lead to one of the world's biggest trade area covering about 3.4 billion people with a combined gross domestic product of about $22.7 trillion, about 30 percent of global output.

When concluded, the RCEP is expected to deliver tangible benefits to businesses through potential improvements in market access, trade facilitation, regulatory reform and more trade-facilitative rules of origin.

While catering to the differences among the 16 countries and providing special policies for the least developed members of ASEAN, observers suggest the RCEP negotiations focus on those areas where a consensus can be reached more easily - similar to the "Early Harvest Program" of the ASEAN-China FTA - so that participating countries can enjoy the benefits as early as possible and will be willing to promote follow-up deals.

At the 18th ASEAN-China, Japan and South Korea (10+3) leaders' meeting on Saturday, Chinese Premier Li Keqiang said that China stood ready to work with other parties to conclude the prolonged RCEP negotiation by 2016 to accelerate trade and regional integration.

He added that China's talks with ASEAN on the upgrading of their free trade area (FTA) will end soon.

The meeting was held weeks after the resumption of the China-Japan-South Korea tripartite summit in Seoul following a three-and-half-year hiatus.

Once implemented, a trilateral FTA will bring together a market of more than 1.5 billion people, raising China's GDP by 2.9 percent, Japan's 0.5 percent and South Korea's 3.1 percent, the Financial Times said.

The planned three-way FTA will expand trilateral and bilateral trade and investment, and provide a comprehensive and institutional framework within which a wide range of trilateral cooperation would evolve.

Over its long way to pursue a truly integrated community, ASEAN has to overcome many obstacles with connectivity, consensus and ASEAN centrality among the core challenges, observers noted.

"The ASEAN Secretariat is an example of a weak institution" which neither has any authority of its own nor any monitoring function, said Sanchita Basu Das, lead researcher on economic affairs at the ASEAN Studies Center of Singapore's Institute of South East Asian Studies.

Therefore, the lack of effective mechanisms in place or being set up in the regional integration plans to ensure accountability from both governments and private sector must be urgently addressed by both ASEAN and its 10 member states.

Otherwise, the efforts to turn ASEAN into a more integrated and outward-looking community that plays a responsible role globally and shares the common destiny will remain elusive.