A Labour government will be "radical and responsible", Jeremy Corbyn will declare as the party sets out its programme for the next five years amid signs it is preparing a tax raid on high earners.
The party is expected to include a £4 billion tax hike for those on more than £80,000 a year to help pay for public services when it publishes its general election manifesto on Tuesday.
Under the plans, the higher 45p rate of tax paid by people with incomes of more than £150,000 would be extended to those on £80,000 while there would be a new 50p top rate of tax, according to The Times and The Daily Telegraph.
The party was also said to be planning a "fat cat" levy on businesses employing staff of hefty pay packages with a 2.5% levy on those on £330,000, rising to 5% for those on £500,000, according to The Guardian.
The Mirror, meanwhile, reported that Labour was planning to extend the 30 hours a week of free pre-school childcare for the working parents of the over-twos to all families at a cost £5 billion a year.
The paper said it was part of a new £12.5 billion-a-year childcare service. There was no immediate comment from Labour on any of the reports.
The party publishes its manifesto having seen many of the main elements already made public following the leak of a draft copy last week, including the renationalisation of key industries, such as the railways and Royal Mail.
The Conservatives said the plans were "nonsensical" and warned that taxes and borrowing would have to rise dramatically to pay for them.
At the formal launch event in Bradford, however, Mr Corbyn will say the party is offering a "radical and responsible" programme while contrasting their support for the "many" to the "mean-spirited" Tories.
"It's a programme that will reverse our national priorities to put the interests of the many first. It will change our country while managing within our means," he will say.
"This is a programme of hope. The Tory campaign, by contrast, is built on one word: fear.
"The Tories are still the nasty party. The party of prejudice, the party of the rich, the party of the tight-fisted and the mean-spirited.
"I am confident that once the people of Britain have the chance to hear our promises and plans, they will decide now is the time for Labour."
For the Conservatives, Treasury Chief Secretary David Gauke said Labour's plans were "nonsensical".
"It's ordinary working people who will pay for the chaos of Corbyn. Jeremy Corbyn has made so many unfunded spending commitments it is clear that Labour would have to raise taxes dramatically because his sums don't add up," he said.
With Labour trailing heavily in the opinion polls, Mr Corbyn needs the manifesto to give his party a fillip if he is to realise his hopes of gaining the keys to No 10 in the election on June 8.
While last week's leak has robbed the launch of much of the drama which normally attends the release of a party's manifesto, the details will nevertheless be closely scrutinised by journalists and political rivals.
According to the leaked draft, it will commit Labour to scrapping university tuition fees, boosting workers' rights and reversing a series of benefits cuts, including the so-called bedroom tax.
To pay for its plans, Labour has said it would take corporation tax to 26% by 2022, bringing in an extra £20 billion, while imposing a "Robin Hood tax" on financial transactions raising another £26 billion, while indicating individuals on more than £80,000 a year will face a tax rise.