US financial watchdog Finra has chosen former SEC trading and markets director Robert Cook as its new chief executive.

Cook, who joins from law form Cleary Gottlieb, replaces Richard Ketchum who has served as Finra’s chairman and chief executive since 2009.

The board intends to name a new chairman in the coming months.

Prior to joining Cleary Gottlieb, Cook served as the director of the division of trading and markets for the SEC between 2010-13.

Under his direction, the division’s 250 professionals were responsible for regulatory policy and oversight with respect to broker-dealers, securities exchanges and markets, clearing agencies and Finra.

Finra regulates brokers and exchanges markets across the US and is tasked with protecting investors.

“Robert has a deep understanding of the securities markets, and investors will greatly benefit from his broad regulatory expertise,” said Finra lead governor Jack Brennan, former CEO of Vanguard Group.

“We thank Rick for his terrific leadership as Finra's chairman and chief executive and express our gratitude on behalf of all investors for his decades of service.”