The head of the newly opened Asia Infrastructure Investment Bank says the China-led group is aiming to approve its first loans before the end of the year, part of Beijing's efforts to weave together regional trade partners.

The AIIB officially opened at a ceremony on Saturday in Beijing, formalizing the emergence of a competitor to the Washington-led World Bank and strengthening China's influence over global development and finance.

China has also pledged an additional $50 million for infrastructure projects in less-developed countries.

AIIB's inaugural president, the Chinese banker Jin Liqun, said Sunday that Asia still faces "severe connectivity gaps and significant infrastructure bottlenecks."

He says the bank would welcome the United States and Japan, two economic powers that have declined invitations to join the organization.