- The actor told Business Insider on Monday: "[Johnson] is a man who simply who does whatever it takes to get him to Number 10 and then keep him there."
- Grant is campaigning for both Liberal Democrat and Labour candidates in the election.
- He says he will not leave the UK "unless I am arrested by a Boris government for sedition."
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Hugh Grant is going door-to-door in the UK general election to persuade British voters against the "terrifying prospect" of a Boris Johnson government.
Canvassing in Westminster on Monday for the Liberal Democrat candidate Chuka Umunna, the actor branded the prime minister "Pinnochio" and told Business Insider that "I really can't see that he has any beliefs at all except Boris Johnson and his career."
Grant, a vocal supporter of keeping the United Kingdom in the European Union, plans to campaign for a series of pro-European candidates in both the Lib Dems and Labour.
He told Business Insider that he was "banging the drum" for tactical voting amid polling in order to prevent Johnson's Conservatives from winning a parliamentary majority on Thursday, December 12.
"I don't think that what's left of the Conservative party once they've now expelled anyone who is responsible or decent or sane is something that I could contemplate as the government for the country I love," he told Liberal Democrat activists.
Grant is urging voters to back pro-Remain candidates who are best-placed to defeat Conservatives. On Sunday he campaigned for Liberal Democrat Luciana Berger and is set to appear alongside Labour's Faiza Shaheen on Wednesday.
Grant said he was concerned that a victory at next week's vote would give Johnson the power to deliver a hard Brexit.
"The very fact that it can be contemplated by Boris Johnson and his gang is a demonstration of just how irresponsible and narcissistic they are and they have to be stopped," he told Business Insider.
He added: "Boris Johnson, or Pinnochio as I call him, is the polar opposite of Chuka in that I really can't see that he has any beliefs at all except Boris Johnson and his career.
"We know that we wrote both a Brexit and a Remain article for The Telegraph on the eve of the referendum. He is quoted in other places pre-referendum as saying of course we must remain. He is a man who simply who does whatever it takes to get him to Number 10 and then keep him there.
"I think that's a very terrifying prospect."
Asked whether he would consider leaving the UK if Brexit goes ahead, Grant said: "I would never want to leave if I can possibly help it unless I am arrested by a Boris government for sedition."
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