Former cabinet secretary Lord O’Donnell has said the position of top civil servant is “massively underpaid”.
He is involved in the recruitment process for the £200,000-a-year role, following Simon Case’s decision to step down on health grounds.
Lord O’Donnell, who held the post between 2005 and 2011, told the BBC the “incredibly demanding job” should have a higher salary.
The cabinet secretary is the UK’s most senior civil servant.
The job involves advising the prime minister, leading implementation of the government’s policies and managing other high-level civil servants.
Speaking to BBC Radio 4’s The Westminster Hour, Lord O’Donnell described the position as a “huge job”.
He said: “It’s massively underpaid in my view – given I’ve been paid a lot more since, to do a lot less.”
Lord O’Donnell served as cabinet secretary under three prime ministers. He was promoted to the post under Tony Blair in 2005, and he remained in the role for Gordon Brown’s premiership between 2007 and 2010.
He stepped down in 2011, under the David Cameron-led coalition government.
Recruitment is under way to replace the current cabinet secretary, Simon Case, who has said he will step down by the end of the year.
Announcing his resignation, Mr Case said he had been undergoing medical treatment for a “neurological condition” for the past 18 months.
He stressed that his resignation was “solely to do with health and nothing to do with anything else”.
Lord O’Donnell said whoever replaces Mr Case will need to have a “good relationship” with the prime minister’s chief of staff, Sue Gray.
“Sue knows the civil service backwards,” he said. “That should be one of the easiest parts of the job, I would say.”
Ms Gray, previously a senior civil servant herself, was at the centre of a row over her own salary in September, after the BBC revealed she is paid £170,000 a year.
This is more than the prime minister, who earns £166,786.