The House of Commons will vote later Wednesday on whether to support May's call for a snap election.
Britain's Prime Minister Theresa May speaks to the media outside 10 Downing Street, in central London, Britain April 18, 2017. TV debates don't have a long history in British politics, but were a feature of the last two elections, in 2010 and 2015.
Theresa May will reportedly include her Brexit negotiating priorities in the Conservative General Election manifesto to lock Remain-backing Tory MPs and the House of Lords into backing her stance.
He told MPs earlier in the Commons: "We welcome the opportunity of a general election because it gives the British people the chance to vote for a Labour government that will put the interests of the majority first".
"It's the right decision, it's in the national interest, and that's what this election is about".
Prime Minister Theresa May said on Wednesday an early election would strengthen her at the "most crucial point" in Britain's divorce talks with the European Union, as she prepared to ask parliament to approve a vote in just seven weeks' time.
She has also played up the strength of the economy, which has so far defied predictions of a slowdown - a key campaign theme that her Conservative Party will use to try to undermine Labour in the election.
Although Parliament will not be officially dissolved until early May, campaigning is already under way - with Lib Dem leader Tim Farron addressing a rally of activists in south-west London earlier on Wednesday.
Corbyn set to fight United Kingdom 'rigged system'
He said Thursday that the election was about "what kind of country we want to have after Brexit". So many people in modern Britain do what seems like the right thing to do.
May, who took office in July after an internal Conservative Party leadership race, wants the election to increase her majority in Parliament and consolidate her power as she faces both pro-EU opposition politicians and hard-core Brexit-backers inside her own party. Its lawmakers abstained during Wednesday's vote.
Meanwhile Jeremy Corbyn is resisting Mrs May's efforts to make Britain's exit from the European Union the defining issue of the election, insisting the poll instead gives voters a chance to pass judgement on the Conservatives' record on austerity and public spending cuts.
Three weekend opinion polls put the Conservatives about 20 points ahead of Labour, and if translated into votes, this could give May an "election landslide" with a majority of more than 100, according to an analysis by The Times. "I will be fighting for them in the seat of a great British newspaper", he said.
Rejecting the PM's claim that an election is needed to prevent disunity at Westminster undermining a Brexit deal, Mr Corbyn said: "There is no obstacle to the Government negotiating, but, instead of getting on with the job, she is painting herself as the prisoner of the Liberal Democrats".
Earlier this month, member countries of the EU signed European Council president Donald Tusk's strict set of guidelines that detail how the bloc will approach negotiations with Britain over its withdrawal from the EU.
A European Commission spokesman said the "real political" negotiations on Brexit will start after the election.
Montgomeryshire MP, Glyn Davies, said the Prime Minister had been left with "little choice" due to frustration over Brexit.
"It is critical that in going into the most significant negotiations in this country for a generation that the Prime Minister has as strong a hand as possible".