The House of Commons has accused John Bercow of naming ex-staff in his autobiography without their permission, saying this was “unacceptable”.
In his book, Unspeakable, the former Commons Speaker hits back at accusations of bullying made against him by individual staff members.
A Commons spokesperson said employees had a “right to expect” privacy.
But Mr Bercow said he was responding to critics who had tried to “blacken” his name by making “unfounded claims”.
He quit as Speaker in October after more than 10 years in the role.
Some of Mr Bercow’s ex-colleagues have gone public with complaints against him in the past.
The Commons has not named the employees it is concerned about.
A spokesperson said: “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. 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.”
In a statement, Mr Bercow’s agent said: “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 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.”
Earlier this week, Mr Bercow confirmed that he had been proposed for a peerage by outgoing Labour leader Jeremy Corbyn.
But he has suggested Downing Street is seeking to block his appointment to Parliament’s upper chamber.