- The Lib Dem leader is today set to tell her party's conference she "cannot wait to take on the collective forces of nationalism and populism" of the prime minister and opposition leader.
- She will describe Johnson's handling of Brexit as "sickening."
- At their conference in Bournemouth, southern England, the Lib Dems vowed to scrap Brexit by revoking Article 50 if they win a majority at the next election.
- Other opposition parties accused the Lib Dems of adopting an undemocratic policy.
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BOURNEMOUTH, ENGLAND Liberal Democrat leader Jo Swinson will on Tuesday say she is ready to take on the "nationalism and populism" of Boris Johnson and Jeremy Corbyn at the next election and become the United Kingdom's prime minister.
In a speech to the Liberal Democrats' conference in Bournemouth, southern England, Swinson is set to say the anti-Brexit party must "seize the opportunity" by winning the next general election and scrapping the UK's EU exit.
Liberal Democrat members on Sunday agreed that the party should scrap Brexit by revoking Article 50 if it wins a majority at the next general election.
"The first task is clear. We must stop Brexit," Swinson is set to say in a speech on Tuesday afternoon.
"And we are crystal clear: a Liberal Democrat majority government will revoke Article 50 on day one."
The member of Parliament for East Dunbartonshire is set to take aim at Prime Minister Johnson and Labour Party leader Corbyn, and accuse the UK's two main political parties of "looking inward at a time of national crisis."
"When the general election comes, I cannot wait to take on the collective forces of nationalism and populism that will be standing on that debate stage. Johnson, [Nigel] Farage, and Corbyn," Swinson is set to say.
Read more: Lib Dems call for Britain's 'disaster ridden' railways to be overhauled in order to save the planet
She is expected to compare the prime minister to a dictator for his "do or die" approach to delivering Brexit, and condemn his "sickening" willingness to take the UK out of the European Union without a deal.
"He [Johnson] prorogued Parliament to try and deny MPs a chance to stop no-deal," Swinson is set to say.
"He's kicked 21 MPs out of the Conservative party, including the Father of the House Ken Clarke, and Churchill's grandson Nicholas Soames. Just because they dared to stand up to him.
"There is even now the suggestion that he would break the law and refuse to ask for an extension to Article 50. Silencing critics. Purging opponents. Ignoring the law.
"For someone who proclaims to hate socialist dictators, he's doing a pretty good impression of one."
She's also expected to attack Corbyn, who "when faced with all the clear and obvious dangers that Brexit brings... still insists that if Labour win a General Election, they will negotiate their own Brexit deal to take us out of the EU."
She'll add: "Nigel Farage might be Brexit by name, but it is very clear that Jeremy Corbyn is Brexit by nature."
Lib Dems defend their hardened Remain policy
The Lib Dems are meeting on the south coast of England after an eventful calendar year, which has seen the party surge in local and European elections, and have five MPs join from other parties in the House of Commons.
The most recent acquisition was former Conservative minister Sam Gyimah, who was unveiled on Saturday .
The party has made headlines at its autumn conference for its policy of scrapping Brexit without a referendum if it wins a majority at the next general election. Other pro-Remain parties including the anti-Brexit Green Party accused the Lib Dems of adopting an "undemocratic" measure.
Green MP Caroline Lucas tweeted : "Brexit referendum didn't deliver the outcome many of us hoped for But you can't pretend the result didn't happen. Lib Dems are doing just that You can't turn back the clock. Nor ignore the 17m who voted Leave This doesn't strengthen our democracy. It further imperils it."
Swinson and other senior Lib Dem MPs insisted that it would not be an undemocratic course of action.
Read more: David Cameron says Boris Johnson backed Brexit to 'help his political career' and lied during the campaign
"If we win a majority in parliament on the very clear position of stopping Brexit then that will be a mandate to do that... People would expect us to fulfill what we've said we would do in that election campaign," she told Sky News.
Chuka Umunna, the party's shadow foreign secretary, said: "This is a general election policy.
"The way our democracy usually works is that you put your promises in a manifesto to the people, and if you get a majority, you implement them. The undemocratic thing would be not to implement your manifesto commitments."
"If you get a majority Liberal Democrat government, why shouldn't we implement our manifesto?"
They also insisted that forcing a new referendum or what campaigners call a People's Vote was still the party's preferred means of keeping the UK in the EU.