Brexit news - live: Boris Johnson vows to secure EU exit if Tories win election, as Lib Dems lay out Remain stance

Only ‘three to four months’ to avoid to avoid no-deal Brexit if PM wins election, legal expert warns

The UK will have only “three to four months” to avert a crash-out Brexit if Boris Johnson passes his deal after an election win, a leading academic has warned.

Catherine Barnard, the professor of EU Law at Cambridge University, told the Commons Brexit committee it was “very unlikely” a complex new trade deal would be agreed by the end of a post-Brexit transition period in December 2020.

Although an extension to the transition must be requested by June 2020, Barnard said “that process of requesting an extension, of course, will have to happen within three to four months of us having left” she told MPs.

And MPs will be powerless to prevent the prime minister pursuing a no-deal at the end of 2020 if he chooses, she said.

Our deputy political editor has all the details.

‘We’re led by a lunatic,’ says one Labour MP

Some Labour MPs are obviously not feeling very energised by the looming election campaign, turning on the boss while speaking to ITV’s Joe Pike.

PMQs begins shortly

We are about to kick off the final PMQs before the election. Here are the MPs who have scored questions to the prime minister.

PM pays tribute to John Bercow

Boris Johnson pays tribute to John Bercow, who is presiding over his last PMQs. Johnson launches into a lengthy tennis metaphor, as Bercow is a huge tennis fan.

He jibes that PM is not being a mere umpire in his 'high chair' but also a 'player'.

"While I have not always agreed with some of your legislative inventions," says the PM with understatement, he praises his record as Speaker.

Richard Braine resigns as Ukip leader

Ukip leader Richard Braine has quit, citing his battles with the party’s national executive committee.

In his resignation letter, Braine wrote: “I did not join UKIP in order to waste time on internal conflict, but I have found myself powerless to prevent a purge of good members from the Party. I had believed that UKIP was a highly democratic party, but I have not been able to stop political interference in UKIP ballots. I cannot therefore stand publicly for UKIP with a clear conscience.”

Johnson hints at changes on fracking

Labour MP Alan Whitehead asks about a report that the Conservative manifesto will be written by a lobbyist for the fracking industry.

Johnson says the government will soon make an announcement about fracking. But this government yields to no one in its enthusiasm to cut carbon emissions, he says.

Jeremy Corbyn pays tribute to the Speaker ahead of clash on NHS

Labour leader says he has turned it from a 'gentleman's club' that happens to be in an old palace, to a truly democratic institution.

He then turns to the prime minister's deal - and a report from Channel 4 News that the cost of medicines has been discussed by UK and US trade representatives. Why did the PM promise the NHS was not on the table?

Johnson says the NHS is not on the table and points to the recent decision to licence Orkambi - a cystic fibrosis drug - for NHS use. He says the government can invest in the NHS because there is a strong economy.

Theresa May rebukes Tory MPs for mocking Corbyn's tie

Jeremy Corbyn presses PM on NHS

Labour leader asks why the cancer treatment waiting times have tripled over the past nine years and also warns that drug prices are rising. He also praises the decision to have Orkambi on the NHS.

Johnson says it is 'satirical' that Corbyn could claim credit over Orkambi being available on the NHS - which he campaigned for. Johnson says the government achieved that not Labour.

Is he so 'phobic' of US companies that he would not hold discussions on drug imports, asks Johnson?

Corbyn says he wants discussions to be done in a transparent way. He turns to early diagnosis rates for cancer and asks why PM doesn't get it.

Johnson says cancer survival rates have increased since 2010 and claims more people are seen within the right waiting times. He accuses Corbyn of talking the NHS down.

Corbyn says A&E departments have had their worst September on record. He asks what winter will be like.

Johnson turns to Theresa May's tried and tested move - comparing the NHS in England to the health service in Labour-run Wales.

Corbyn says he is surprised the PM can keep a straight face after the government cuts to the Welsh government budgets. He accuses the PM of having a 'brass neck'.

Johnson hits back, saying it's easy to be an "Islingtoner" who sides with Russia - and accuses the Labour leader of "flip flopping" on all the important issues.

"The time for protest is over, the time for leadership is now," he says.

David Lidington to stand down

Theresa May's former deputy PM David Lidington has announced he is stepping down at next election.

“After a great deal of thought I have decided not to seek re-election at the forthcoming general election."

"Politics imposes a heavy cost on family and private life," he told his local newspaper.