The chief executive of the giant Dutch civil service pension fund ABP is standing down for personal reasons.

Henk Brouwer on Thursday announced his intention to quit on June 1. A spokesman for the fund, which is one of the biggest in the world, declined to go into further details.

The news of Brouwer’s departure has surprised industry figures, the Financieele Dagblad says. The paper also says there is no division between Brouwer and the rest of the management team in terms of policy.

Brouwer, born in 1946, has chaired the fund since January 2012. Deputy chairmen José Meijer and Cees de Veer will take over his duties until a new chairman has been appointed.