Video report by ITV News Political Correspondent Libby Weiner
Labour’s policies would cost £1.2 trillion over five years, the Conservative Party has claimed as it gears up for the second week of the General Election campaign.
Chancellor Sajid Javid said the opposition's pledges would leave the country with an economic crisis "within months".
The Tories' £1.2 trillion figure is based on costing Labour's 2017 manifesto and other pledges it has made since then.
But the Labour Party has yet to publish its 2019 election manifesto, detailing its policies and spending proposals.
As a result, Labour has condemned the analysis as a "ludicrous piece of Tory fake news" and an "incompetent mish-mash of debunked estimates and bad maths".
Speaking to BBC One's Andrew Marr show, Mr Javid said if Labour are elected on December 12, it would amount to an extra £650 million a day or "something like the entire NHS budget for nine years."
He said: "This is the true cost of Corbyn's Labour: these are the numbers that John McDonnell did not want you to see, and they're out there today...
"These are eye-watering levels of spending - £1.2 trillion.
"It will be absolutely reckless and will leave this country with an economic crisis within months, not years."
The Chancellor told the Sunday Times the country “cannot afford Corbyn’s spending spree”, which he claimed would “undo all the hard work of the British people in recent years”.
He said Labour’s proposals – which include plans to renationalise rail, mail, water and energy – could leave the economy on the “brink of bankruptcy”.
Business minister Kwasi Kwarteng told Sky's Sophy Ridge On Sunday that Labour's spending plans were "reckless" and "unaffordable."
However, he could not state the total cost of the Tories' pledges.
"I'm not going to bandy around figures," he said.
"It's absolutely right for us to say this is what the opposition are saying and this is how much it is going to cost."
The paper said the figure was based on costings for Labour’s last manifesto and its most recent pledges, spread across a five-year period.
Shadow chancellor John McDonnell labelled the claims a “ludicrous piece of Tory fake news” and an “incompetent mish-mash of debunked estimates and bad maths cooked up because they know Labour’s plans for real change are popular”.
He said: “Labour will tax the rich to pay for things everyone needs and deserves, like decent housing, healthcare and support for our children.
“We will also use the power of the state to invest to grow our economy, create good jobs in every region and nation and tackle the climate emergency.
“The Conservatives will be able to read all about these plans – and how much they actually cost – when we publish our fully-costed manifesto.”
Shadow defence secretary Nia Griffith said Labour would not implement every policy from its annual conference, as she dismissed the £1.2 trillion figure from the Tory claim as "absolutely ludicrous".
She told Sky: "We're not going to be implementing every single thing that was in our conference in this manifesto...
"You can only do a certain amount at once, can't you?"
And Labour's Andrew Gwynne told the BBC's Andrew Marr show the figures are "an absolute work of fiction by the Conservatives."
"You can't trust a word that Johnson and his ministers say on this issue," he said.
"We will have a fully-costed manifesto in due course when we launch that, and the challenge actually is for the Conservatives to fully cost their own manifesto, something they didn't do in 2017."
Mr Gwynne said the correct figure for Labour's spending is "still being finalised."
It comes as the Tories revealed plans to quadruple the number of migrant workers that can take up seasonal work on British farms from next year.
The Sunday Telegraph reported that the Prime Minister has approved plans to allow fruit and vegetable farmers to hire up to 10,000 workers from outside the EU for temporary roles.
Party leaders will display a rare moment of unity as they pause their campaigns to pay their respects at the National Service of Remembrance at the Cenotaph on Sunday morning.
Labour is considering plans for a universal basic income in its “most radical” manifesto yet, shadow chancellor Mr McDonnell told the Independent newspaper.
Brexit Party leader Nigel Farage warned the Tories the “clock is ticking” to secure a Leave alliance at the General Election.
The Lib Dems are proposing to scrap settlement fees for Armed Forces veterans who were born outside the UK, while the Tories have said veterans will be eligible for a railcard giving them a third off the cost of train travel.
Elsewhere, Steve Baker, the chairman of the European Research Group of Tory Brexiteers, urged voters to “seize the opportunity to get Brexit done”, warning: “It’s now with Boris or it’s never.”
Writing in the Sunday Express, he said: “Only the Conservative Party can deliver Brexit in this election. A vote for any other party is effectively a vote for Jeremy Corbyn.
“That is because the Brexit Party cannot win a majority. It might not even be able to win a seat. But it is capable of splitting the Leave vote so that Jeremy Corbyn gets into power.”