Nikko Cordial Corp., the nation's third-largest brokerage, became a subsidiary of Citigroup Inc. on Wednesday as the U.S. financial giant completed its acquisition through a public tender offer, company officials said.

Citigroup now has a stake of more than 61 percent in Nikko Cordial, including the 56.2 percent it bought in a public tender offer that closed in late April.

The U.S. firm has indicated it plans to purchase all remaining Nikko Cordial shares to turn the Japanese brokerage into a wholly owned subsidiary.

Citigroup and Nikko Cordial have set up committees to work out specific business cooperation arrangements.