White & Case London executive partner Oliver Brettle has stepped down from his role with immediate effect, after a decade leading the US firm's City office.

London capital markets partner Melissa Butler has been appointed to replace him as London head, taking up the new post yesterday (8 May). Butler, who joined the firm in 2006 and made partner in 2012, also leads the firm's Africa interest group.

Brettle will remain on the firm's executive committee and will focus on expanding the London office.

White & Case chairman Hugh Verrier said: "I have asked Oliver Brettle in his ongoing role on the executive committee to focus on delivering our 2020 strategy, including global initiatives that support its execution and strengthen the firm's competitive position vis-à-vis the magic circle.

"To allow him to dedicate the time needed to drive these important activities, Oliver has stepped down as London office executive partner after nearly 10 years in the role, during which time our London office has become an acknowledged market leader. I am proud of our success in London. "

Brettle added: "Holding the role of London office executive partner has been a wonderful experience and a privilege, working with exceptional lawyers and business services teams who together deliver the highest standard of service to our clients. I look forward to continuing to work closely with Melissa Butler and wish her every success in her role."

Brettle first joined the firm from Ashurst in 2001 as a partner. He was appointed as London office head in 2008 and joined the executive committee in 2009.