HighTower Advisors, a firm that is expanding by poaching financial advisers from the big brokerages, on Monday said it hired a private banking team from Merrill Lynch managing more than $1 billion of client assets.

HighTower's latest additions are Paul Pagnato and David Karp of Washington, D.C., two advisers from Merrill's private banking and investment group that caters to rich investors.

Pagnato founded Merrill's private banking office in Washington and served on the Merrill Lynch advisory board. Karp was a member of Merrill's investment policy committee.

Chicago-based HighTower, which launched in December 2008, said the Pagnato-Karp group represents its first private banking hires. The firm's more than 50 financial advisers now help manage about $20 billion in client assets.

Merrill was acquired by Bank of America (BAC.N) in January 2009, a deal that placed Merrill's private banking group and BofA private bank unit U.S. Trust under the same roof.

HighTower CEO Elliot Weissbluth in May told Reuters he expects the pace of breakaways from big brokerages such as Merrill will begin to accelerate because retention deals signed by advisers in 2008 and 2009 are gradually losing their grip.