The Regional Comprehensive Economic Partnership (RCEP) arrangement was initially expected to be inked by the 10-member ASEAN and six other states this week.
But the Singaporean official said at the opening of an RCEP meeting that talks on the world’s largest trade pact had taken "much longer than usual," according to Channel News Asia.
READ MORE: ASEAN Summit Kicking Off in Singapore
Lee Hsien Loong assured the gathering that the deal would be concluded next year. He warned that difficulties were unavoidable but the "benefits will be equally substantial."
The Association of Southeast Asian Nations, which comprises Singapore, Indonesia Malaysia, Philippines, Thailand, Brunei, Vietnam, Laos, Myanmar, Cambodia, hopes to strike the deal with China, Japan, South Korea, India, Australia, and New Zealand.