John Bercow has been elected Speaker of the House of Commons after defeating Sir George Young in the final round of voting tonight.

The divisive MP for Buckingham defeated his fellow Tory comfortably by 322 votes to Sir George’s 271. Standing in front of the green Speaker’s chair shortly before 9pm, Mr Bercow thanked those who had backed him.

“You have just bestowed on me the greatest honour that I have enjoyed in my professional life,” he said. “I thank you for the confidence you have placed in me. I am keenly aware of the obligations into which I now enter,” he said, promising to serve the House faithfully and impartially.”

Mr Bercow said the House did need to be reformed, but insisted that the vast majority of MPs were “decent honourable people”.

The Prime Minister, who by convention did not vote, congratulated Mr Bercow on becoming the 157th Speaker. He said the House had taken an “important step” in the “process of change”. “You will bring a strength of character and purpose to this House,” he told MPs shortly before 9pm.

David Cameron, the Conservative leader, also congratulated his colleague, saying: “We share a collective responsibility for what went wrong, we share a collective responsibility for putting it right.”

The Commons now expects a controversial period where Mr Bercow, who was elected by Labour votes for the most part, tries to prove that he is capable of uniting the House.

Mr Bercow and Sir George were left to fight it out after eight other candidates either dropped out or were eliminated in two previous rounds of voting. Mr Bercow topped the second ballot, boosting his support from 179 to 221. However, Sir George kept himself in the contest by racking up 62 extra backers to reach 174.

Among those to drop out was Margaret Beckett, the former Foreign Secretary, who had been favourite to win the contest. Another was Ann Widdecombe, who hoped to do the job until her retirement at the next election, and who was eliminated with just 30 votes.

Alan Beith and Sir Alan Haselhurst pulled out after the second round while, in the first round of voting, four candidates were ejected. Sir Michael Lord came bottom with just nine votes, three less than the number of those who supported him on his nomination paper, while Sir Patrick Cormack (13 votes), Richard Shepherd (15) and Parmjit Dhanda (26) were also forced out.

Giving his speech to a packed Commons earlier, Mr Bercow drew laughter as he joked about his bid to become Speaker at the relatively young age of 46.

He pledged to stay in place for a maximum of nine years if elected and described himself as the “clean-break” candidate, who was ready and willing to bring about change.

Speaking without notes, Mr Bercow said: “I want to implement an agenda for reform, for renewal, for revitalisation and for the re-assertion of the core values of this great institution in the context of the 21st century.”

Mrs Beckett had been tipped to win the contest, and her elimination indicates that a whipping operation led by Nick Brown, the chief whip, had failed.

Times Recommends

• What makes the perfect mum?
• To keep me stress-free, no more awareness days, please
• What do lottery winners buy?