John Bercow has served as speaker of parliament's lower chamber for 10 years.

John Bercow, the speaker of Britain's House of Commons, announced Monday that he would step down within weeks, amid criticism by Brexit hardliners who say he has twisted parliamentary rules to undermine them.

Bercow said he would not stand again if MPs vote later Monday in favour of an early general election -- and if they do not, as seems likely, he would resign on October 31: the scheduled date for Brexit.

Bercow has served as speaker of parliament's lower chamber for 10 years, overseeing heated debates on Brexit and making decisions as to what the house should do, based on centuries of precedent.

"If the house votes tonight for an early general election, my tenure as speaker and MP will end when this parliament ends," Bercow told the chamber.

"If the house does not so vote, I have concluded that the least disruptive and most democratic course of action would be for me to stand down at the close of business on Thursday, October 31."

Bercow is best known for presiding over debates, bellowing "Order! Order!" at unruly lawmakers and humorously chastising MPs who irk him.

He has sought to modernise parliament, abandoning the speaker's traditional robes for a simple gown over a suit, and seeking to make it easier for female MPs with new babies.

But critics say he is pompous, biased in favour of anti-Brexit MPs, and overly fond of the sound of his own voice.

Bercow said the timing of his departure would mean that MPs would have some knowledge of the candidates to replace him.

He also said it would be better than after a general election, when new MPs may come under party influence in their choice of the next speaker.

"I have sought to increase the relative authority of this legislature, for which I will make absolutely no apology," Bercow told MPs.

"This is a wonderful place filled overwhelmingly by people who are motivated by their notion of the national interest, by their perception of the public good, and by their duty, not as delegates, but as representatives to do what they believe is right for our country.

"We degrade this parliament at our peril."