A senior Chinese official has urged the United States to join the China-led Asian Infrastructure Investment Bank (AIIB) instead of keeping on questioning the proposed bank’s transparency and governance.

Zhang Jun, a senior Chinese official who is in charge of China’s International economic portfolio, issued the invitation on the heels of statements by the US officials that the proposed AIIB will weaken the status of existing global institutions such as the World Bank and the International Monetary Fund (IMF).

“I believe both China and the AIIB welcome the United States in joining the AIIB. But if the United States still needs time to wait and see, I think it’s OK. The AIIB will be able to move forward according to its schedule and plan,” Zhang told journalists.

A number of US allies, including European countries such as the UK, Italy, Germany and France, have already declared their interest to join the AIIB, with plans to invest money into the bank.

Australia’s cabinet has also approved the country’s plan to join the AIIB and sign the memorandum of understanding with China before the Chinese-set deadline of 31 March. The deadline is for those who want to be founding members of the bank.

While some US officials have declared that the AIIB will challenge the standing of the IMF and the World Bank, the world’s top financial institutions said they will support the USD$50-billion investment bank.

Asian Development Bank President Takehiko Nakao, IMF Managing Director Christine Lagarde and WB Managing Director Sri Mulyani Indrawati said their institutions are ready to cooperate with the AIIB, which was earlier described by the US as an attempt to stomp on existing financial institutions.

Most of AIIB’s regional members joined last year and China earlier announced a 31 March deadline for those who want to join as founding members. The AIIB, which is expected to begin operations by the end of 2015, is formed to provide infrastructure project loans to developing countries.