RIO DE JANEIRO - Brazil said on Friday it had accepted China's invitation to join its Asian Infrastructure Investment Bank (AIIB) as a founding member.

"Brazil is very interested in participating in this initiative," the office of President Dilma Rousseff said in a short statement. It said no conditions were made for joining.

The AIIB has been seen as a challenge to the World Bank and Asian Development Bank, and a significant step for China's global influence. China is Brazil's top trading partner.

The United States had warned against the new institution but its European allies Britain, France, Germany and Italy announced this month they would join the bank, leading the Obama administration to reassess its stance.