John Bercow, the speaker of the House of Commons, has rowed with prominent Brexiteer Andrea Leadsom, calling the cabinet minister a “stupid woman” in the Commons chamber this week.

The speaker, who is anti-Brexit and promised to ban U.S. president Donald J. Trump from the Commons, is currently facing calls to be investigated over numerous bullying claims.

Some MPs also say they heard him mutter that Mrs. Leadsom, the leader of the House of Commons, was “f***ing useless”, though others present disputed that claim, The Times reports.

The Speaker’s Office played down the exchange, saying simply that “strong and differing views were expressed on all sides”.

John Bercow goes on a tirade in the Commons before allegedly calling Andrea Leadsom 'stupid' Read more: https://t.co/OhIfZ8BCxd pic.twitter.com/0S5J50K5Ol — The Telegraph (@Telegraph) May 17, 2018

The alleged row comes days after MPs blocked an inquiry into Mr. Bercow’s behaviour after he was accused of viciously bullying his former private secretaries over a long period of time.

Andrew Bridgen, the Tory MP for North West Leicestershire and a fierce critic of Mr. Bercow, said:

“His behaviour is becoming more extreme and bizarre by the day. He portrays himself as a champion of political correctness, feminism, and diversity, except of course when he’s attacking the Conservatives.

“John Bercow has got to go now – for the sake of our democracy.”

A Commons source said: “Mrs. Leadsom did not hear the remark herself but was left stunned when told about it by outraged colleagues.”

Conservative MP @JamesDuddridge says John Bercow promised to step down as Speaker in June, and asks for debate about the role of Speaker. Mr Speaker says he indicated his willingness to continue in post and he was elected unanimously. pic.twitter.com/76IKcGEx3j — BBC Parliament (@BBCParliament) May 10, 2018

The source added: “She is very keen to rise above it and not let it distract from other very serious and worrying claims about bullying made in parliament.”

A source close to Mrs. Leadsom said: “Andrea is absolutely determined to see the independent complaints procedure up and running as soon as possible.

“As for Bercow’s terrible temper, it would be completely unacceptable to treat someone like that in any other walk of life.”

The Conservative MP Daniel Kawczynski said: “The Speaker is showing increasing signs of anger and frustration towards ministers and it is frankly unbecoming of his position. I am prepared to back the calls for him to go.”