China's past experimental approach to infrastructure growth applied to the Asian Infrastructure Investment Bank (AIIB) would help economic growth across borders, a German economist said at a think tank in Washington.

"The infrastructure problem has been neglected for decades," Sandra Heep, head of Economic Policy and Financial System program at the Mercator Institute for China Studies in Berlin, said at the Johns Hopkins School of Advanced International Studies on Wednesday. "One prominent feature of China's development experience is its experimental approach to solving these problems."

"From a German perspective, I think we should make such a great deal of China's AIIB initiative, because it is completely a bank with expectations," Heep said. "China is taking this experimental approach beyond boarders and maybe they would apply the approach within the multilateral institution. AIIB will be the solution the problem of infrastructure investment money."

AIIB, the China-led multilateral investment bank that will provide financing for roads, railways, airports and other infrastructure projects in Asia, finalized its prospective founding members at 57 on Wednesday, according to China's Ministry of Finance.

Latest approved founding members are Sweden, Israel, South Africa, Azerbaijan, Iceland, Portugal and Poland, making the membership map cover five continents: Asia, Oceania, Europe, Latin America and Africa.

Heep said it should be appreciated that "China is willing to exercise part of its influence through multilateral financial institutions" since it would "inevitably come to play a more influential role in the global financial architecture".

"To better integrate China into global financial governance, the West should support China's AIIB initiative and help the country to become a responsible stakeholder," she said.

Daivd Dollar, a senior fellow at the Brookings Institution, said that it's "logical" for China to start creating a competing institution.

"We should welcome the fact that China is creating some new multilateral institutions," said Dollar, who is also a former US Treasury Department economic and financial emissary to China. "It is a largely positive development."

A leading expert on China's economy and China-US economic relations who had worked at the World Bank for more than 20 years, Dollar praised the AIIB as a "good opportunity to create a more efficient development bank".

"The current multilateral banks are not perfect," he said. "The Chinese have said for a long time that they would like to see the World Bank focus more on infrastructure growth and lots of developing countries which borrow from the World Bank feel it is very bureaucratic and slow."

"So there is a lot of potential to improve efficiency," he continued. "I predict the AIIB will have a positive effect on the existing model of multilateral banks."

Though the deadline for founding membership application passed on March 31, the bank will continue to accept new ordinary members with voting rights but less say in the rule-making process.

The AIIB has drawn the attendance of some key US allies.

Sheng Yang in Washington contributed to this story.