The House of Commons has hit out at John Bercow for naming members of staff in his autobiography without their permission.
A spokesman said it was “unacceptable” for the former speaker to identify current and ex-members of staff for “the purpose of financial gain or commercial success”.
“House of Commons staff work incredibly hard to enable the effective functioning of our democracy and have a right to expect that their privacy be respected,” they said.
“It is unacceptable to publicly name current or former staff without their prior knowledge or authority, especially for the purpose of financial gain or commercial success.
“A crucial element of the work of House of Commons staff is to provide confidential, impartial advice to MPs.
“Breaking this confidentiality undermines this important principle and also places staff in a position from which they are unable to respond.”
But a spokesman for Mr Bercow defended his decision to name members of staff.
“Given there is a small but highly vocal group of people consistently seeking to blacken his name, it would be odd if Mr Bercow did not comment on their unfounded allegations and the reasons behind them,” he said.
“He was advised by Speaker’s Counsel not to do so in detail while he was in office. He is therefore doing so now.
“If the book had not addressed these issues, he would rightly have been accused of serious omission.
“Critics are entitled to air their views. What they are not entitled to do is to make unfounded allegations and expect Mr Bercow to say nothing in return.”
Mr Bercow stepped down as speaker in November after 10 years in the role.
His autobiography, Unspeakable, was published on Thursday.
It comes as Mr Bercow faces allegations of bullying from two senior parliamentary officials – former clerk of the House Lord Lisvane, and the former Black Rod, David Leakey.
He strongly denies the allegations against him.
In an exclusive interview with Sky News earlier this week, Mr Bercow said accusations he “brutalised” parliamentary staff and politicians were “total and utter rubbish”.
Mr Leakey stands by his claims.
The row with the Commons could impact on Mr Bercow’s hopes of entering the House of Lords.
Downing Street broke with the tradition of offering a retiring speaker a place on the red benches, in a sign of the irritation within Number 10 at Mr Bercow’s time in the speaker’s chair.
He has since been nominated by outgoing Labour leader Jeremy Corbyn.
Mr Leakey told Sky News the former speaker entering the House of Lords would be “a scandal that parliament would struggle to live down”.