Britain's House of Commons Speaker John Bercow, who played a key role in the three-year Brexit crisis, said on Monday he would stand down from the role, issuing a warning to the government not to “degrade” parliament.

Bercow bent parliamentary rules to give lawmakers the chance to challenge government policy, most recently to pass a law seeking to block a no-deal exit from the European Union.

He was given a standing ovation from many members of the lower house as he announced his plan to stand down in the coming weeks.

A member of parliament since 1997, he has been speaker since June 2009 and has often been a thorn in the government's side.

He has overseen heated debates on Brexit and making decisions as to what the house should do, based on centuries of precedent.

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,” he said, with his gaze fixed on the benches in the debating chamber where government members sit.

Prime Minister Boris Johnson has been heavily criticised for suspending parliament for just over a month, only weeks before the country's most important political decision in decades.

Bercow said he would not contest the next election if parliament voted later on Monday in favour of calling one. If, as expected, lawmakers reject the government's attempt to call an election, he said he would quit on October 31 — the day Britain is currently due to leave the EU.

“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.”