Could Russell Brand decide the UK election?

The leader of the U.K.'s opposition Labour party has tried to give his election campaign a celebrity boost by meeting with comedian, actor and political activist Russell Brand to talk…tax.

The interview between Labour leader Ed Miliband and Brand – due to be uploaded Wednesday to the latter's YouTube channel "The Trews" -- features the pair discussing democracy, multinational taxation and spending cuts.

In a trailer released by Brand Tuesday, he asks Miliband what he would do to tackle multinational companies who use complicated arrangements to minimize the amounts they pay in tax.

"We've got to deal with that. You need to do it internationally, because these companies are mobile around the world and you have to be willing to act in the way you can," Miliband said. "It doesn't mean it's easy in a world where capital and companies are mobile, but of course you can deal with these things and people share your outrage."

The Labour leader was seen leaving Brand's flat in east London, with four bodyguards, Monday, when the interview is thought to have taken place.

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But the meeting seems somewhat counter-intuitive as Brand -- a campaigner known for his blunt views on politics – told the BBC in 2013 that he had never voted, and never would.

"I am not voting out of absolute indifference and weariness and exhaustion from the lies, treachery and deceit of the political class that has been going on for generations," he told the news channel.

The interview is also seen as a cynical move by Miliband to attract younger voters.

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With Brand's 9.5 million Twitter followers, his comments will certainly pack a punch and the interview has shifted the spotlight on to Miliband with just days to go until the general election on May 7.

'Gimmicks' and 'jokes'

The comments come as political parties appear to be resorting to increasingly desperate measures to attract voters. Polls show that the Labour and Conservative parties are close in the polls– although Miliband has edged slightly ahead of Conservative leader and current Prime Minister, David Cameron, over the last few weeks, according to IG's Election Barometer and other polls.

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Responding to the interview, Cameron, who is seeking re-election on May 7, called both his opponent Miliband and Brand "a joke."

Russell Brand
Photographer | Collection | Getty Images

"His whole view is 'don't vote, it only encourages them', or something," Cameron said during a campaign speech Tuesday. "It's funny, but politics, life and elections and jobs and the economy are not a joke…I haven't got time to hang out with Russell Brand. This is more important."

But Miliband insisted that the meeting had made the election campaign more "interesting."

"What is a joke is saying this election is about leadership and then refusing to debate," he said on the campaign trail in south Wales Tuesday. "I am surprised by David Cameron, I just think he is totally out of touch. Some people have said this campaign is boring so I have decided to make it more interesting."

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Showing that the Conservatives might not be above headline-grabbing antics themselves, David Cameron is expected to pledge to ban tax rises until 2020 on Wednesday.

Cameron hopes the tax promise will inject momentum into his campaign, by highlighting the party's commitment to low taxes, but on Tuesday, Labour's press team tweeted that the Conservatives were resorting to "desperate gimmicks."

- By CNBC's Holly Ellyatt, follow her on Twitter @HollyEllyatt.