BEIJING, Jan. 16 (Xinhua) -- Two years have passed since the Asian Infrastructure Investment Bank (AIIB) started operation, and the steady expansion of membership represents a vote of confidence in the new multilateral bank by the international community.

Since its launch in January 2016, AIIB's approved membership has risen from 57 to 84, expanding its reach within Asia and across the world.

Headquartered in Beijing and with authorized capital of 100 billion U.S. dollars, AIIB is a multilateral development bank focused on infrastructure investment, with a mission to improve social and economic outcomes in Asia and beyond.

As it starts its third year of operation, officials from the bank promised to further expand membership and strengthen its role in the international financial community.

Following are some of the milestones and achievements in the AIIB's past two years of operation.

-- On Jan. 16, 2016, representatives of the 57 founding countries of the AIIB gathered in Beijing for the opening ceremony in Diaoyutai State Guesthouse.

With joint efforts by all members, the AIIB aims to become a lean, clean and green development bank for the 21st century.

-- In June 2016, the bank approved its first four loans, totaling 509 million U.S. dollars, to fund power, housing and transportation projects in Bangladesh, Indonesia, Pakistan and Tajikistan.

-- In September 2016, a groundbreaking ceremony for the permanent headquarters of the AIIB was held in Beijing.

The headquarters will be located in the north of Beijing, between the Olympic Forest Park and the iconic Bird's Nest Stadium, with construction expected to be completed by the end of 2019.

-- In March 2017, the AIIB board of governors approved 13 applications to join the bank, the first time the bank has welcomed new prospective members since its inception, bringing the bank's total membership to 70.

-- In May 2017, the AIIB Board of Governors adopted resolutions approving seven applications to join the bank, bringing its total approved membership to 77.

-- In June 2017, the AIIB approved three applications at its second annual meeting of governors, bringing its total approved membership to 80.

-- In 2017, the AIIB received three top-notch ratings from the global credit rating agencies S&P Global Ratings, Moody's and Fitch in recognition of the bank's strong capital base and stable outlook.

-- In December 2017, the AIIB approved its first loan in China for a natural gas project.

The 250-million-U.S. dollar loan will fund a project to connect 216,750 households in approximately 510 villages to the natural gas distribution network.

In the two years the AIIB has been operating, it has invested in 24 projects in 12 countries, with loans exceeding 4.2 billion U.S. dollars.

-- In December 2017, the AIIB Board of Governors approved 4 applications to join the bank, bringing its total approved membership to 84.