Doctors have joined picket lines outside Huddersfield Royal Infirmary as they begin the first all-out strike in the organisation’s history.

There were more than a dozen pickets outside the main approach to the Infirmary in Acre Street shortly after 8am this morning.

And the picture was repeated across the country, with medics walking out on strike.

READ MORE: Junior doctors' strike: Live updates from the Huddersfield picket line

Banners carried by the pickets shouted: “Protect NHS staff” and “Fight the junior contracts” as the row over proposed new contracts escalated.

Thousands of junior doctors have begun the first all-out strike in the history of the NHS after the Health Secretary said the Government would not be “blackmailed” into dropping its manifesto pledge for a seven-day health service.

Jeremy Hunt appealed directly to medics yesterday not to withdraw emergency cover, which he said had particular risks for A&E departments, maternity and intensive care.

READ MORE: Doctors don't want to work in HRI or CRH because they're so understaffed, says A&E chief

READ MORE: Junior doctors walk out of Huddersfield and Calderdale hospitals in second wave of strikes

The impasse between the Government and the British Medical Association (BMA) prompted the industrial action, from 8am to 5pm today and again on Wednesday.

It is the first time services such as A&E, maternity and intensive care have been affected during the dispute over a new contract.

Speaking on BBC Breakfast, Mr Hunt accused union leaders of trying to “blackmail” the Government with strike action.

He said he could only call a halt to the action “by abandoning a manifesto promise that the British people voted on” at last year’s general election.

The Health Secretary said: “It was the first page of our manifesto that we’d have a seven-day NHS.

“I don’t think any union has the right to blackmail the Government, to force the Government to abandon a manifesto promise that the British people have voted on.”

Despite an intense three days of letters back and forth and a phone call between Mr Hunt and the head of the BMA on Monday, no agreement on a way forward has been reached.

READ MORE: Junior doctors strike: Passers-by show solidarity with striking staff at Huddersfield and Calderdale hospitals

READ MORE: Doctors on strike in Huddersfield and Calderdale

Mr Hunt said he was motivated by a desire to improve weekend services in the NHS and told MPs that “no trade union” had the right to veto a Government manifesto commitment to do so.

He said the disruption over the next two days is “unprecedented” but the NHS has made “exhaustive efforts” to ensure patient safety.

He said: “No trade union has the right to veto a manifesto promise voted for by the British people.”

Picket line outside Huddersfield Royal Infirmary as junior doctors' strike begins.

Accident and emergency Dr Tom Roberts, 28, said he was striking because of the “unfair and unsafe” contract proposed by the Health Secretary that would leave many doctors “underpaid and over-stressed”.

Dr Roberts, originally from Perthshire, told the Press Association: “We believe this contract will spread doctors too thinly across the ground and the NHS, from August if he goes through with this, will be unsafe for everybody.

“The BMA and junior doctors ... have asked Jeremy Hunt on so many occasions to just come and talk again, and he just tweeted responses to well-meaning questions.

“It is very, very frustrating for us. He just doesn’t want to face doctors, he doesn’t want to talk to us.”