Kemi Badenoch has said the Conservatives will ban strikes by all NHS doctors if they return to power.
The Tory leader said her party would introduce legislation for minimum service levels and block doctors taking widespread industrial action, placing them under the same restrictions that apply to police officers and soldiers.
Dr Tom Dolphin, chair of the British Medical Association trade union, called the proposal “a desperate intervention from a Conservative Party that spent nearly 15 years failing the NHS”.
Thousands of resident doctors, formerly junior doctors, began a five-day strike on Friday after the government and British Medical Association (BMA) failed to reach an agreement over pay.
In the UK, the only people legally prohibited from going on strike are members of the police force and non-civilian members of the armed forces. Doctors have the same right to strike as any other employee in the public or private sector.
The previous government passed a law requiring minimum service levels in certain sectors, including some health services, but only ever got as far as considering it for doctors.
The BMA says that despite a 5.4% average pay rise this year, following a 22% increase over the previous two years, pay is still down by a fifth since 2008 once inflation is taken into account.
A pay uplift of 26% is needed to reverse real-term wage decline, the union says.
But announcing her policy on Sunday, Badenoch accused the union of becoming “more and more militant”, adding that the pay rise resident doctors had already received was “well above anything that any other group has had”.
“Doctors do incredibly important work. Medicine is a vocation, not just a job. That is why in government we offered a fair deal that supported doctors, but protected taxpayers too,” she said.
“That is why Conservatives are stepping in, and setting out common sense proposals to protect patients, and the public finances.
“We are making an offer in the national interest – we will work with the government to face down the BMA to help protect patients and the NHS.”
Dr Dolphin said industrial action was a “last resort” for doctors and “fundamentally the right to strike should always be there”.
“Threatening to ban strike action is not the right response for a modern democracy,” he added.
The BMA and NHS England have an agreed process for hospitals to request striking doctors return to work in the event of an unforeseen emergency or mass casualty event, Dr Dolphin said.
He continued: “That process is there day and night throughout industrial action, and we remain ready to respond to any emergency requests.”
Ahead of the beginning of strike action, Health Secretary Wes Streeting said the government would “not let the BMA hold the country to ransom” and insisted that disruption in the NHS would be kept to a minimum.
NHS England had ordered hospitals to only cancel non-urgent work in exceptional circumstances.
No official figures have been released yet on the impact of the latest strike. Some hospitals are reporting more than 80% of non-urgent work is still being done with senior doctors covering for resident doctors.
But several patients have told the BBC operations which had been scheduled during and around the strike period had been cancelled or postponed.
The Conservative party claims that its proposed changes would bring the UK in line with other nations across the world, such as Australia and Canada, which have much tighter restrictions on industrial action.
Others like Greece, Italy and Portugal also have laws ensuring minimum service levels are in place across their health services, but the BMA said the party’s argument was “misleading”.
The BBC has approached Labour for comment on Badenoch’s proposals.
