SINGAPORE (Reuters) - Founding members of the China-backed Asian Infrastructure Investment Bank (AIIB) will hold a three-day meeting in Singapore, starting Wednesday, to discuss operational policies for the establishment of the institution.

The gathering, called the 5th chief negotiators' meeting, will also discuss the draft articles of agreement for the AIIB, the Ministry of Finance (MOF) announced on Tuesday.

The meeting will be co-chaired by Shi Yaobin, vice minister of China's Ministry of Finance, and MOF deputy secretary Yee Ping Yi.

A total of 57 countries have joined AIIB as its founding members, China has said, throwing together countries as diverse as Iran, Israel, Britain and Laos.

Among the Group of Seven (G7) industrialized countries, the United States, Japan and Canada remain absentees.

Washington had cautioned nations about joining the bank, seen as a rival to the US-dominated World Bank, citing what it called a lack of transparency, doubts about lending and environmental safeguards, and concerns over Beijing's influence.

Beijing says it will not hold veto power inside the AIIB, unlike the World Bank where Washington has a limited veto.

Founder members will initially pay up to one-fifth of the AIIB'S US$50 billion authorised capital, which will eventually be raised to US$100 billion.