Two star private equity partners at Sidley Austin, including its practice co-head, have quit the firm.

Private equity co-head and buyout specialist Erik Dahl and private equity partner Christian Iwasko have left the U.S. firm after four years.

Dahl joined Sidley's Munich base to lead its operations there, while Iwasko joined the firm's London office. Four other Kirkland partners made the move with the pair.

Mike Schmidtberger, chair of Sidley's executive committee said in a statement: "Our partners, Erik Dahl in Munich and Christian Iwasko in London, have resigned from the firm. We wish them well.

"We have a deeply experienced and very active team of private equity lawyers in London, Munich and the U.S. with a wide range of clients. This practice has been a major source of growth for us globally, it is built to last and we will continue expanding our capabilities in this area."