Labour's Wes Streeting has accused the Tories of intentionally planning to lose the next election.
It comes as Labour leader Sir Keir Starmer said that he will use his party's conference later this month to set out a "road map for Britain".
The comments by Wes Streeting, Labour's shadow health secretary, come just days before the Conservative Party announces is new leader and the country gets a new prime minister.
Foreign Secretary Liz Truss is widely tipped to defeat Rishi Sunak, taking charge in Downing Street with a general election not scheduled until January 2025.
Mr Streeting, in a lengthy interview with the Telegraph newspaper, said that he is confident Labour is going to win the next general election and predicted that the Tories will intentionally try to lose.
Mr Streeting, seen as a potential future leader of the party, told the Telegraph: "I think the Conservatives are planning to lose the next general election."
According to the newspaper, the 39-year-old points to the decision by the current Government to cap the number of medical students as evidence for his claim.
The Conservatives have "concluded there's no point recruiting medicine trainees because they're not going to come into work until there's a Labour government in place. I think that's recklessly short-sighted", he is quoted as saying.
"I don't know what other explanation there is. For them to turn away bright young people from university places they desperately want to take up. That is threatening the future pipeline. We should be developing our homegrown talent for the NHS."
Only last month Education Secretary James Cleverly defended the Government's refusal to lift the cap on medical student admissions this year and insisted it was increasing NHS recruitment.
Elsewhere in the interview, Mr Streeting hit out at Tory plans for the NHS as he indicated that extra funding for the health service would have to come with some kind of reform.
"There's no doubt in my mind - and this is why Liz Truss is being dishonest with the public - that there isn't a fix to the NHS crisis that doesn't involve more investment," he told the paper.
"This is a bit more difficult for a Labour audience to hear, there isn't a fix for the NHS in the long term that can involve huge amounts of extra money every year. Because at that point, the NHS begins to look unsustainable. We can't just keep on pouring in more money."
Discussing his own successful treatment for kidney cancer, he said: "We can't let our reverence [for the NHS] prevent us from making the changes that are needed to make it fit for the 21st century."
"With the best will in the world, there are always producer interests that creep in and I will have no truck with producer interest.
"There will always be people in the system who say, 'But that's not how we do things'. I want to work with the system rather than to fight the system. But, ultimately I'll always do what's in the best interest of patients."
His party leader, who this week turned 60, used an interview with the Mirror to offer a sense of Labour's vision for the country.
He told the paper: "I am going to set out in my conference speech our road map, our plan for Britain and how Labour will give Britain the fresh start it needs."
He promised plans that include "fixing the short-term problems like the cost-of-living crisis, the National Health crisis and the law and order crisis", while also looking ahead to rebuilding the economy and tackling the climate crisis.
