LUXEMBOURG, July 15 (Xinhua) -- The Asian Infrastructure Investment Bank (AIIB) needs time to "build capacity," and therefore it must take a cautious approach to development, the head of the banking institution recently told Xinhua.

The AIIB members have various requests, and a relatively large difference in their requests exists between the developing countries and the developed, AIIB President Jin Liqun said. "We have limited funds, so it's hard to solve all the problems overnight."

Though not all of their expectations can be fulfilled in the short term, the institution will continue its efforts to expand the camp of borrowers and promote infrastructure construction and sustainable development, Jin said.

Jin made the remarks after the fourth annual meeting of the AIIB's Board of Governors concluded in Luxembourg on Saturday. During the meeting, the AIIB expanded its membership to 100 with the approval of the African newcomers of Benin, Djibouti and Rwanda.

The China-initiated multilateral financial institution began operation in January 2016 with 57 founding members, with an agenda focused on supporting sustainable development through infrastructure and other productive sectors in Asia and beyond.