During their monthly meetings, Curiel would ask Franco to sign documents in English that Franco could not understand, including an International Swaps and Derivatives Association agreement that facilitated the foreign exchange and option transactions, the complaint alleges.

FORBES: Mexican Investor Blames Citigroup For $50 Million In Personal Losses

Achieving that sum likely will depend on getting agreement from countries that hold large foreign exchange reserves, such as China and Saudi Arabia.

WSJ: Wen Voices Concern Over China's U.S. Treasurys

Guo Shuqing, the head of the China Securities Regulatory Commission, said that the regulator had already reached an agreement with the Chinese central bank and the State Administration of Foreign Exchange to raise the QFII limit.

BBC: Chinese yuan notes