WASHINGTON, March 31  -- The United States stands ready to welcome the China-proposed Asian Infrastructure Investment Bank (AIIB), U.S. Treasury Secretary Jacob Lew said Tuesday, just after his two-day visit to Beijing.

"We have made clear to China that the United States stands ready to welcome new additions to the international development architecture, including the Asian Infrastructure Investment Bank, provided that these institutions complement existing international

financial institutions and that they share the international community's strong commitment to genuine multilateral decision making and ever-improving lending standards and safeguards," Lew said in a speech at the Asia Society Northern California.

"I was encouraged by my conversations in Beijing in which China 's leaders made clear that they aspire to meet high standards and welcome partnership," Lew said, adding that having the AIIB co- finance projects with existing institutions will help demonstrate a commitment to the highest standards of governance, environmental and social safeguards, and debt-sustainability.

While details are pending, China has repeatedly stated that the AIIB will uphold high standards and learn from the best practices at existing multilateral financial institutions.

The AIIB will be compatible with established international lenders, Chinese Foreign Ministry spokesperson Hua Chunying said Tuesday, adding that the founding of the bank "will complement the current international economic order and enable China to shoulder more global responsibility."

Lew also said the United States welcomes China's growing involvement in the global economic architecture, as China assumes a more significant role on the international stage. "To be clear, China and other emerging markets deserve to have their voices heard. They will have an important role in setting rules and standards for the multilateral system in the future."

The AIIB, expected to be formally established by the end of 2015, will be an international financial institution to fund infrastructure projects in Asia. China confirmed on Tuesday that 30 countries have been approved as prospective founding members of the AIIB.