Paul Wolfowitz, World Bank president, has called on staff to treat the bank's investigations unit as an "ally" helping to root out corruption rather than a "watchdog" that held the staff under suspicion.

Mr Wolfowitz's appointment last week of Suzanne Rich Folsom, a counsellor in his office with close ties to the Republican party, to head the Department of Institutional Integrity has provoked objections within the bank about her suitability for the post - and about the process for appointing her to a sensitive and senior position.