Tim Farron says 80% of people will feel they didn't vote for the Brexit outcome.

Richmond & Twickenham Times

A huge upset has been pulled off by the Liberal Democrats, with Sarah Olney defeating Zac Goldsmith in the Richmond Park and North Kingston by-election., external

Claire Timms
BBC London News

Labour MP for Tottenham David Lammy says the lesson from the Richmond by-election is "the views of 16m people matter and there is real concern about Brexit. In a democracy their voice must be heard".

Tory MP Jacob Rees-Mogg, talking to BBC Radio 4's Today programme says Remain supporters in Richmond Park are disgruntled about the majority of the country going against them.

Conservative MP Grant Shappshas revealed he believes it was a mistake for the party not to field a candidate against Zac Goldsmith.

The London Assembly's only Liberal Democrat politician Caroline Pidgeon has is revelling in Sarah Olney's shock win.

The Liberal Democrat leader Tim Farron says his party are "carrying the torch" for the people who didn't vote for an "extreme version of Brexit".

Liberal Democrat Sarah Olney beat independent Zac Goldsmith in the Richmond Park by-election.

Guardian political columnist Rafael Behr gives his take on Sarah Olney's victory in Richmond.

The Daily Telegraph

The Liberal Democrats have won the Richmond Park by-election, pulling off one of most spectacular political upsets of recent years and denting the Conservatives' narrow majority in the House of Commons. , external

Chris Mason
Political Correspondent

Image source, AFP/Getty Images

In a year of political upsets, another.

Sarah Olney joined the Liberal Democrats only 18 months ago. She now becomes the party's ninth MP.

As soon as the polls closed last night, the width of Lib Dem smiles pointed to an extraordinary result.

A party of government shrivelled to a rump at last year's general election had rediscovered its mojo in this rich, pro-European corner of south-west London.

Zac Goldsmith had hoped this contest would be a referendum on the prospect of even more planes thundering through the skies here if Heathrow Airport gets bigger.

But, instead, it was June's EU referendum that dominated.

Seventy per cent of voters here backed Remain. But Zac Goldsmith didn't. The Liberal Democrats, unapologetically pro-EU, ruthlessly exploited this.

Sarah Olney told me she would vote against triggering Article 50 - the formal mechanism for starting Brexit.

But the country voted Leave, even if this seat didn't, and the government will press on regardless.

For Zac Goldsmith this was his second political humiliation of the year.

Beaten by Labour to be London Mayor, beaten by the Lib Dems in his own backyard. And leaving Theresa May's slender majority looking even thinner.

Liberal Democrat leader Tim Farron said: "This was a remarkable, come-from-nowhere upset that will terrify the Conservatives.

"A year and a half ago, their man won by nearly 40% and had a majority of more than 20,000.

"In one fell swoop we have wiped that out completely."

Labour's Richmond Park candidate Christian Wolmar says the Liberal Democrats' win is a vote against Zac Goldsmith's mayoral campaign, in which he lost to Labour's Sadiq Khan earlier this year.

Mr Wolmar received just 1,515 votes so lost his £500 deposit as he didn't win a big enough share of the vote.

Ex-Tory MP Zac Goldsmith gives a speech after losing to Liberal Democrat Sarah Olney in the Richmond Park by-election.

Mr Goldsmith, standing as an independent, polled 18,638 votes to the Liberal Democrat's 20,510.

Tom Moseley
Political reporter

Image source, Getty Images

The by-election in Richmond Park was the 28th since 2010.

Here's how they all ended.

Susana Mendonca
BBC Radio London Political Reporter

Image source, PA

The Richmond Park and North Kingston by-election result shows the price that can be paid for taking a political gamble when you don't have to. 

Zac Goldsmith paid that price and the disappointment on his face was clear as the result was announced. 

There were no interviews with the media scrum that gathered around him. He just moved quietly and sombrely out of the hall and into a waiting car.

This is a man who's lost two elections this year - first the London mayoral race, and now the very constituency where he'd been an MP for six years.

He said the decision to spark a by-election wasn't politically motivated. That he'd done it because he'd made a promise on Heathrow and he had hoped the voters would back him on that. 

The trouble with elections though is that voters aren't always voting on the issues politicians want them to vote on. And in this case the triumphant Lib Dems say Brexit was the defining factor. 

Around 70% of voters in the area  backed remaining in the EU, while Zac backed leaving - and the Lib Dems who are pro remaining - say that stood in their favour. 

Zac Goldsmith's defenders say he was at a disadvantage because as an independent candidate he didn't have the Tory machine behind him getting the voters out, while the Liberal Democrats put everything into this election. 

Image source, PA

The new MP Sarah Olney certainly is not a household name. She's new to politics and this is the first time she's stood for Parliament, so her personal brand is unlikely to have swung it for the Lib Dems, but nonetheless she managed to decimate the 23,015 vote majority that Zac Goldsmith had won just a year ago - despite the Conservatives and UKIP not running candidates against him to help him out. 

Sarah Olney's beaming smile said it all as she walked into the hall before the official result was announced. In her acceptance speech she said the voters had given her a mandate to challenge the Tory government on Brexit. 

But in reality it did more than that: a Liberal Democrat win in what had been a safe Tory seat is likely to send a shiver down Theresa May's spine as she contemplates whether the gamble of calling an early General Election is a risk worth taking.

• Sarah Olney (Liberal Democrats) - 20,510
• Zac Goldsmith (Independent) - 18,638
• Christian Wolmar (Labour Party) - 1,515
• Howling Laud Hope (The Official Monster Raving Loony Party) - 184
• Fiona Natasha Syms, (Independent) - 173
• Dominic Francis Stockford, (Christian Peoples Alliance) - 164
• Maharaja Jammu and Kashmir (One Love Party) - 67
• David Powell - 32

Turnout = 53.6%

Ms Olney was elected with a majority of 1,872 votes, compared to a Conservative Party majority of 23,015 at the 2015 General Election.

In her victory speech, political novice Lib Dem Sarah Olney said it was last year's General Election result which first prompted her to get involved.

"I think a lot of people in this community had the same feeling this summer. Richmond Park is full of people like me who felt that something was going wrong. That the politics of anger and division were on the rise. That the liberal, tolerant values we took for granted were under threat. 

"We were seeing the UKIP vision for Britain in the ascendancy – intolerant, backward-looking, divisive; just as we see it in America and across Europe.

"Well today we have said no. We will defend the Britain we love. We will stand up for the open, tolerant, united Britain that we believe in. 

"The people of Richmond Park and North Kingston have sent a shockwave through this Conservative Brexit Government. 

"And our message is clear: we do not want a ‘hard Brexit’; we do not want to be pulled out of the Single Market; and we will not let intolerance, division and fear win." 

The Lib Dems poured resources into the contest as they successfully switched the focus of the campaign to Brexit in the staunchly Remain west London seat after Zac Goldsmith quit as a Tory MP to force the by-election so he could run as an anti-Heathrow expansion independent. 

The result saw Sarah Olney poll 20,510 votes to Mr Goldsmith's 18,638, on a turnout of 41,367, or 53.6%. 

The 21.74% swing to the Lib Dems from Mr Goldsmith topped the 19.3% swing they achieved from the Tories in the Witney byelection. 

Ms Olney took 49.7% of the vote.

Liberal Democrat leader Tim Farron described Sarah Olney's Richmond Park by-election win as "remarkable".

"The message is clear: The Liberal Democrats are back and we are carrying the torch for all of those who want a real opposition to this Conservative Brexit government.

"This was a remarkable, come-from-nowhere upset that will terrify the Conservatives. A year and a half ago, their man won by nearly 40% and had a majority of more than 20,000. 

"In one fell swoop we have wiped that out completely. 

"If this was a general election, this swing would mean the Conservatives would lose dozens of seats to the Liberal Democrats - and their majority with it."