-- ASEAN and its partners on Tuesday launched negotiations of a comprehensive partnership agreement that when completed will be the world's biggest regional free trade deal, an official statement launched here said.

Australia, China, India, South Korea, Japan and New Zealand officially kicked off negotiations for the Regional Comprehensive Economic Partnership or RCEP at the final day of the 21st ASEAN Summit and related summits.

The idea was first mooted at the 19th ASEAN Summit in November 2011.

The significant progress made in ASEAN's FTAs with China (ACFTA) , Japan (AJCEP), South Korea (AKFTA), India (AIFTA), and Australia and New Zealand (AANZFTA) has put these trading partners in a position to bring to a higher level economic partnership.

When completed, the RCEP will span 16 countries with a combined market of over 3 billion people and a combined GDP of about 19.78 trillion U.S. dollars based on 2011 figures.

"With the region accounting for more than half of the global market and about a third of the global economic output, there is no doubt that a successful RCEP would significantly contribute and boost global trade and investment," said Dr. Surin Pitsuwan, Secretary-General of ASEAN.

The landmark event in Phnom Penh comes at a time when economic recovery efforts continue to be seriously challenged by the volatile global financial and economic situation.

RCEP negotiations are expected to commence in 2013.

In addition, it was reported that South Korea, China and Japan had also agreed to form a free trade agreement at the summit, which is expected to formally begin next year.

Smaller countries such as Myanmar progressed on economic agreements. On Monday, Thailand and Myanmar signed a joint agreement to move ahead with the multi-billion dollar Development of Dawei Special Economic Zone (DSEZ) in Myanmar