Johnson, Corbyn square off in 1st debate ahead of early U.K. election

Prime Minister Boris Johnson and opposition Labour Party leader Jeremy Corbyn squared off Tuesday in the first live televised debate of the U.K.'s election, each trying to spark a lackluster campaign to life.

No clear winner as leaders spar over Brexit and U.S. trade deals

U.K. Prime Minister Boris Johnson and Labour Party Leader Jeremy Corbyn answer questions during the ITV leaders debate on Tuesday in Salford, England. (Jonathan Hordle/ITV via Getty Images)

Prime Minister Boris Johnson and opposition Labour Party leader Jeremy Corbyn squared off Tuesday in the first live televised debate of the United Kingdom's election, each trying to spark a lacklustre campaign to life.

The hour-long encounter — the first head-to-head TV debate between a prime minister and a chief challenger — offers Corbyn a chance to make up ground in opinion polls, which show his Labour Party trailing Johnson's Conservatives ahead of the Dec. 12 election.

For Johnson, it's a chance to shake off a wobbly start that has seen the Conservatives thrown on the defensive by candidates' gaffes and favouritism allegations involving Johnson's past relationship with an American businesswoman.

Speaking in front of a live audience at the studios of broadcaster ITV in Salford, northwest England, the two men traded blows over the U.K.'s stalled departure from the European Union — the reason the election is being held. The U.K. is due to leave the bloc on Jan. 31, after failing to meet the Oct. 31 deadline to approve a divorce deal.

Johnson blamed the opposition for "dither and delay, deadlock and division" and said a Conservative government would "end this national misery, break the deadlock and get Brexit done."

Corbyn said a Labour government would also settle the Brexit question by negotiating a new divorce deal with the bloc before holding a new EU membership referendum within six months.

WATCH: Johnson and Corbyn spar over Brexit in testy leadership debate

Prime Minister Boris Johnson shook hands with his rival, opposition Labour leader Jeremy Corbyn, during a live television debate on Tuesday as both men agreed to improve the tone of the U.K.'s political debate. 2:27

Corbyn — a lifelong critic of the EU and lukewarm advocate of the U.K.'s membership in the bloc — did not answer when asked repeatedly by Johnson whether he would support leaving or remaining in a new referendum.

The Labour leader, meanwhile, slammed Johnson's claim that he would negotiate a new trade deal with the EU by the end of 2020 as a fantasy, saying such deals usually take years to complete.

"You're not going to get it done in a few months, and you know that perfectly well," Corbyn said.

The debate featured only two candidates after the High Court in London rejected a legal challenge from two smaller anti-Brexit parties, the Liberal Democrats and the Scottish National Party, over ITV's decision to exclude their leaders from the debate. The court decided it was a matter of "editorial judgment" to limit the format to the leaders of nation's two largest political parties, one of whom will almost certainly be the country's next prime minister.

Later in the campaign, the leaders of smaller parties will take part alongside Labour and the Conservatives in two seven-way debates, and Corbyn and Johnson are due to square off again in a BBC debate on Dec. 6.

Johnson answers questions about Brexit and relations with the U.S. during the leaders debate. ( Jonathan Hordle/ITV via Getty Images)

The stakes are high for both Johnson and Corbyn as they try to win over a Brexit-weary electorate. Both are trying to overcome a mountain of mistrust.

Johnson, 55, limbered up Tuesday by donning boxing gloves emblazoned with his campaign slogan "Get Brexit done" during a visit to a gym.

Corbyn, 70, was photographed having his beard trimmed at a barber shop and said he prepared for the debate with a Caesar salad and "a couple of cups of tea."

Johnson — an ebullient but erratic performer — is under fire for failing to deliver on his vow that the U.K. would leave the EU on Oct. 31. Corbyn, a stolid socialist, is accused by critics of promoting high-tax policies and of failing to clamp down on anti-Semitism within his party.

Televised debates are a relatively new phenomenon in U.K. elections — the first took place in 2010 — and they have the power to transform campaigns. A confident 2010 appearance by former Liberal Democrat leader Nick Clegg sparked a wave of "Cleggmania" that helped to propel him into the deputy prime minister post in a coalition government with the Conservatives.

During the last election in 2017, then-prime minister Theresa May refused to take part in any TV debates. The decision reinforced the view that she was a weak campaigner, and the election turned out to be a debacle for her Conservative Party, which lost its majority in Parliament.

The stalled departure from the EU is the overriding issue in the Dec. 12 vote. Johnson pushed to hold the election more than two years ahead of schedule in an effort to win a majority in the House of Commons that could pass his divorce deal with the EU.

More than three years after the U.K. voted to leave the 28-nation bloc, the terms of the country's departure and its future relationship with the EU remain unclear. The U.K. is now scheduled to leave on Jan. 31 after the EU granted a three-month delay amid gridlock in Parliament over Johnson's Brexit deal.

All 650 seats in the House of Commons are up for grabs. Smaller parties in the race include the pro-EU Liberal Democrats, who want to cancel Brexit; the Scottish National Party, which seeks Scotland's independence from the U.K.; the anti-EU Brexit Party led by Nigel Farage; and the environmentalist Greens.

The Tuesday night debate came as political parties were launching their election platforms.

Labour plans to release its manifesto on Thursday, promising a much bigger role for the state in the economy. Party economy spokesman John McDonnell told the BBC Labour would tackle society's "grotesque levels of inequality."

Johnson's Conservatives accuse Labour of peddling failed socialist ideas. But in a major policy shift, the Conservatives are also wooing voters with promises of more public spending on health, education and infrastructure after almost a decade of cuts and austerity budgets.

The Tory campaign has been dented by a renewed focus on allegations that Johnson gave favours and public funding to U.S. tech entrepreneur Jennifer Arcuri — with whom he had a relationship — while he was mayor of London between 2008 and 2016. Johnson has insisted that "everything was done with full propriety."