Bank of America’s Andrew Sieg, currently head of retirement services, will now also lead the firm’s global investment solutions unit as Kunal Kamlani steps down.

Bank of America Merrill Lynch’s head of retirement services Andrew Sieg has been appointed to also serve as head of the firm’s global investment solutions unit, a spokesperson for the firm confirmed.

The new appointment comes as Kunal Kamlani, who currently serves as the head of the global investment solutions unit, has decided to step down from that position and leave Bank of America. Sieg’s expanded role and Kamlani’s departure were first reported by Bloomberg on Thursday, citing an internal memo from Bank of America President of Global Wealth and Investment Management Sallie Krawcheck.

Sieg was reportedly considered for the role as head of U.S. Wealth Management, which ultimately went to John Thiel in April. Sieg joined Bank of America in September 2009 from Citigroup Inc., where he served as managing director of an emerging affluent client segment within global wealth management.

Kamlani took on the leadership role over the global investment solutions unit, which manages investment products, in March 2010. Before that, he held positions including chief financial officer at Prestige Cruise Holdings Inc. and chief operating officer at Smith Barney.