The AIIB's door has been opened and the door will stay open, said Jin Liqun, president of the Asian Infrastructure Investment Bank (AIIB), at a press conference on Sunday.

Jin made the remarks in response to a question about whether the AIIB's door is open to Japan and the United States.

"I'm very grateful to all the governments of the member countries who have been supporting, and I am grateful to all the governments of the countries which are on the waiting list, and we will try to resolve their membership issues as soon as possible," Jin said.

The press conference was held after the conclusion of the two-day inaugural meeting of the AIIB's board of governors, which approved by-laws, rules and codes of conduct for the bank.

Thirty of the 57 prospective founding members, representing over 74 percent of the shares, have ratified the article agreement, thus becoming full members of the AIIB, and the remaining ones will have completed their membership processes by the end of this year, Jin said.

"This bank is warmly embraced by so many countries in the world. We have member countries in every continent, from north to the south, from east to the west, it is truly a great achievement," he said.

The new multilateral financial institution was proposed by Chinese President Xi Jinping in 2013 and officially established late last year. It is headquartered in Beijing.

With authorized capital of 100 billion U.S. dollars, the AIIB prioritizes investment in energy, power generation, transportation, rural infrastructure, environmental protection and logistics.