Kemi Badenoch has pledged to block long-term benefits claimants from spending taxpayer cash on alcohol, cigarettes and gambling under Tory plans to slash the welfare bill.

The package would also see the Conservatives only pay out full Universal Credit (UC) to long-time claimants if they have made consistent contributions to the welfare state to clamp down on a system that Mrs Badenoch says is “unfair to workers”.

Under the Tory plans, anyone who claims UC when they are out of work would get six months of full benefits to find a job.

After that, the full rate would only be available to people who have contributed to the welfare system through their taxes for years.

Those who have not would have their UC standard rate slashed by a third and the payment would be loaded onto a “back to work” pre-payment card, which would ban spending on cigarettes, alcohol, betting and cash withdrawals.

Mrs Badenoch said: “Some will say this is unfair on people claiming benefits. What is unfair is a system where someone who can work chooses not to and earns more from benefits than someone in a job.

“If you can work, you should work. Helping people into work is not punishment. The best welfare is a well-paid job. So, we will be tough on those who exploit the system because the current system is unfair to workers, taxpayers and those who truly need support.

“We should not be borrowing from our children and grandchildren to support people who simply refuse to work.

“Welfare must be a safety net for those who genuinely need it, not a lifestyle choice for those who can’t be bothered.”

The reforms could save the taxpayer £538 million a year by moving 350,000 benefits claimants onto a new “subsistence allowance”, the Tories estimate.

The party sought to justify its plans by suggesting it was unfair for taxpayers to shoulder the costs of long-term jobless benefits claimants.