The Philippines is among the five remaining countries – and the last in Southeast Asia – which have not joined a China-led multilateral lending organization for infrastructure development.

Beijing-based Asian Infrastructure Investment Bank (AIIB) concluded its 7th chief negotiators meeting in Frankfurt, Germany last week, where the country sent a delegation as among prospective members tasked to draft the bank’s rules and regulations.

On the sidelines of the meetings, Malaysia and Thailand became AIIB’s newest members with their signing of the Articles of Agreement, the bank said on separate statements on its website.

As a result, 52 of 57 prospective members already formally entered AIIB. Five continues their observer status and will have until Dec. 31, 2015 to join. These countries are Denmark, Kuwait, the Philippines, Poland and South Africa.

National Treasurer Roberto Tan, who led the country’s delegation, did not respond to questions for comment. Charles Jose, spokesperson for the Department of Foreign Affairs, also did not return calls and messages. Details