The rift between the medics' union and the Government has deepened after the British Medical Association voted not to re-enter negotiations over the proposed contract for junior doctors.
The BMA's UK junior doctor committee voted not to re-enter contract negotiations with NHS Employers, with the union claiming the current offer is "unacceptable".
Health Secretary Jeremy Hunt has given the BMA until September to negotiate changes to working contracts for hospital consultants and junior doctors to ensure "proper" seven-day services, warning that he is ready to impose a new contract if they cannot agree.
NHS Employers said it was "extremely disappointed" with the BMA's position.
The BMA called for the Government to reverse its "hardline" stance, warning that the proposed contract could lead to junior doctors working dangerously long hours, putting patients at risk.
Dr Kitty Mohan, the BMA junior doctor committee co-chair, said: "The Government has said it wants to negotiate but this 'offer' on the table is an imposition in all but name. It would be letting down our members and the patients for whom they care to simply go along with a Government hell-bent on getting something signed, sealed and delivered as quickly as possible.
"This is simply unacceptable. Junior doctors are not prepared to agree contract changes that would risk patient safety and doctors' well-being. This was our position in October and - in the absence of any attempt by the Government to address our concerns - remains our position today.
"We want a contract that is good for patients, fair for doctors and good for the NHS. That means instead of imposing changes on junior doctors, the Government should put aside its artificial deadlines, its imposed recommendations and work with the BMA on genuine negotiations."
Key measures the BMA want reversed include proposals to extend routine working hours from 60 hours per week to 90, with the union insisting it will not accept that "working at 9pm on a Saturday is viewed the same as working at 9am on a Tuesday".
The BMA argues that the contract removes vital safeguards which discourage employers from making junior doctors work "dangerously long hours", and the proposal would no longer match pay with the experience junior doctors' gain through their training.
The decision on the junior doctors' contract will not affect the separate deal for the most senior medics, with the BMA's consultants' committee weighing up the options of a negotiated settlement.
NHS Employers chief executive Danny Mortimer said: "As the BMA know, our approach to contract discussions has always been based on providing safe working hours for doctors in training, as well as stability of pay and agreed and fair work schedules.
"Whilst the Doctors and Dentists Review Body endorsed the broad direction of travel, there was still much to do, and we accepted their encouragement to discuss these issues - including the BMA concerns - further.
"Employers across the NHS are extremely disappointed to hear that the BMA junior doctor committee have decided to refuse to enter contract negotiations with NHS Employers. While consultants continue to engage in productive negotiation with us it is a real shame that we do not see the same approach from junior doctors."