Speaker John Bercow has been reported to the Commons' standards watchdog over claims he branded Andrea Leadsom a "stupid woman" and "f****** useless".
Tory MP James Duddridge said he had made a formal complaint to Parliamentary Commissioner for Standards Kathryn Stone over the May 16 outburst in the chamber directed at the Commons Leader.
Mr Bercow on Monday admitted using the word "stupid" but offered no apology.
He said he would "continue to speak out firmly" for the interests of the Commons and publicly disagree with the Government's management of business, which is led by Mrs Leadsom.
In his letter to the Commissioner, Mr Duddridge said he believed Mr Bercow's actions breached the Commons' 2009 code of conduct, which states: "Members shall at all times conduct themselves in a manner which will tend to maintain and strengthen the public's trust and confidence in the integrity of Parliament and never undertake any action which would bring the House of Commons, or its Members generally, into disrepute."
The Rochford and Southend East MP wrote: "We cannot let the current situation of intimidation and bullying from such a senior figure whom we should look to set an example and act as arbitrator.
"The perpetrator cannot be allowed to have so much power over the House, its members and staff who work in the Commons. It is essential that the Speaker steps aside from chairing and participating on all matters related to bullying."
He also asked for a call to evidence over "intimidating behaviour which I and other members have witnessed repeatedly over the years".
The Commissioner's office confirmed it had received a complaint and she would "consider whether the matter is within her remit and, if it is, whether there is sufficient evidence to justify beginning an inquiry".