Clifford Chance has guided the Bank of Tokyo-Mitsubishi UFJ and Mitsubishi UFJ Securities Holdings on the $480 million buyout of Bank of America Merrill Lynch’s stake in their Japanese private banking joint venture, Mitsubishi UFJ Merrill Lynch PB Securities.

Japan's biggest bank will buy Merrill Lynch's 49 percent stake in the private banking venture formed in 2006 for an undisclosed sum, the companies said in a statement.

A source with direct knowledge of the matter said the value of the deal is about 40 billion yen ($482.3 million).The joint venture had an operating revenue of 25 billion yen and a net profit of 6.8 billion yen for the year ended in March 2012.

The value of its deposited assets stood at 1.8 trillion yen as of that date, the statement said.Tokyo partner Tatsuhiko Kamiyama led Clifford Chance’s team on the transaction, assisted by counsel Yusuke Abe.

Separately, MUFG plans to buy 20 percent of VietinBank from the Vietnamese government for about 60 billion yen ($720 million), another source told Reuters, as Japan's cash-rich big banks expand into fast-growing Southeast Asian markets.

Kanishk Verghese is North Asia journalist at ALB. Follow us on Twitter: @ALB_Magazine.