Susan Martin, CEO at Local Pensions Partnership, London, resigned effective Tuesday, a spokesman said.
Chris Rule, managing director and CIO, was named interim CEO, the spokesman confirmed. Mr. Rule is retaining his current responsibilities at LPP alongside the CEO duties.
Ms. Martin will be returning to consulting, the spokesman said.
"We'd like to thank Susan for her significant contribution to the establishment and success of LPP and wish her the very best for the future," said Michael O'Higgins, LPP chairman, in a news release.
LPP, a pool of U.K. local authority pension funds, had £17 billion ($22 billion) in assets as of Dec. 31.