Junior doctors will hold a fresh ballot for more strike action, according to reports, as the longest walkout in NHS history ends on Tuesday morning.

The British Medical Association’s (BMA) junior doctors committee has plans to hold a third vote for a new six-month mandate for industrial action over the long-running pay dispute, according to The Guardian.

The move is likely to increase tensions in the health sector which have already been heightened by the record six-day strike.

The current mandate was voted for by members in the summer and expires on February 29 and union sources say support among junior doctors for continuing their campaign remains strong, according to the newspaper.

The BMA would not comment on the reports when approached by the PA news agency.

The latest junior doctors’ strike in England, due to come to an end at 7am on Tuesday, has caused “delay and disruption” to thousands of patients according to health bosses.

On Monday, Health Secretary Victoria Atkins said she would sit down to negotiate with junior doctors if they enter talks with “reasonable expectations”.

She told the Commons it is time for the junior doctors committee to “show that they’re serious about doing a deal”.

The Prime Minister previously backed calls by hospital bosses for junior doctors to leave picket lines and return to work amid patient safety fears.

A number of hospitals in England pleaded for medics to return to work due to safety concerns – also known as derogation requests.

On the first day of the strike, critical incidents were declared at Queen Alexandra Hospital in Portsmouth and by the NHS in Nottingham.

Meanwhile, more than a dozen hospitals said that emergency services were busy, with some reporting “extreme heightened pressure”.

NHS England chief executive Amanda Pritchard praised staff who have worked throughout the action – including junior doctors who either chose not to take action or returned to work to ensure patient safety was maintained.

In an update sent to NHS leaders, she said patients in need of time-sensitive treatment “are left shouldering the greatest personal risk” – including those with cancer.

She said more “repeated periods of ever-more drastic action” is “not sustainable”.

Ms Pritchard said: “I’ve heard accounts of colleagues all the way from the front line to service and board directors working around the clock – and in unfamiliar settings – to keep services running and patients safe.

“I include in that the many junior doctors who have chosen not to take action, or who have returned to work to ensure minimum levels of cover, whether or not formal patient safety mitigations were granted.

“Ultimately, despite the best efforts of everyone in the NHS, it is inevitably patients – many needing time-sensitive treatment – who are left shouldering the greatest personal risk.”

NHS officials have said that the impact of the strike could be felt for weeks or months as services try to catch up on lost time due to the walkout.

The BMA has said junior doctors’ pay has been cut by more than a quarter since 2008.

Junior doctors in Northern Ireland are being balloted for the first time over potential strike action.

If BMA members vote for strike action, medics will stage a 24-hour full walkout, the BMA’s Northern Ireland junior doctors’ committee said.

Meanwhile, junior doctors in Wales are set to stage a 72-hour walk out from Monday January 15.

Junior doctors in Scotland settled their pay dispute last summer.