“It is time for a laser-like focus on winning our clients’ investment assets,” to expand beyond their traditional banking and lending needs, Sieg wrote. He will address investors later Wednesday in his first remarks at a public conference since joining Citi in September.

Bitterly, who currently leads investment solutions, will succeed Joe Ryan, who is running the Wealth at Work business on an interim basis after the departure of Naz Vahid was announced last month.

Sieg has pushed a growth strategy based on capturing the estimated $5 trillion in assets that Citi’s wealthy clients have invested with other banks or asset managers. Read more on this topic.