Bank of America's Merrill Lynch cut its number of national business divisions to six from 10 and changed some of the executives leading those units as part of a broader leadership restructuring, according to a memo sent to employees.

The head of Merrill Lynch Wealth Management Andy Sieg told the firm's roughly 14,500 brokers that the plans, which went into effect immediately, were part of an effort to "make the organization feel like a smaller, more tightly integrated firm."

The change, designed to create fewer, larger market regions, will not reduce the number of financial advisers at the firm. The announcement was first reported by The Wall Street Journal.

South Atlantic division head Don Plaus will now lead Merrill Lynch's Private Banking & Investment Group for ultra wealthy clients. Ben Prince, who had led the Southwest division, will head up Merrill's strategy to develop local market opportunities for around 150 small branches, according to the memo.

Two Merrill market executives Lindsay DeNardo Hans and Vince Fertitta were promoted to lead the Mid-Atlantic and Texas Mountain South divisions respectively.

Jeffrey Tucker, formerly the New York City Metropolitan division head, and Tom Fickinger, previously head of the Pacific Northwest division, will both take other jobs within Merrill that have not yet been announced.

Linda Houston, who headed the New England division, will retire, and James Dickson, who had led the Mid East division, is leaving the firm.

Apart from the regional leadership changes, Mike Adornetto was named Merrill Lynch's new chief operating officer and Hong Ogle will lead the firm's adviser training and development programs.