Boris Johnson left open the possibility of a U-turn on the low pay rise for NHS workers.

The Prime Minister defended his Government's decision to only award a 1% pay rise to NHS staff, despite calls for a higher increase in the wake of the Covid-19 pandemic.

But, as he spoke to reporters in North London on Sunday, Mr Johnson revealed the pay decision is not final.

Mr Johnson told broadcasters: "I’m massively grateful to all NHS staff and indeed to social care workers who have been heroic throughout the pandemic.

“What we have done is try to give them as much as we can at the present time.

“The independent pay review body will obviously look at what we’ve proposed and come back.

“Don’t forget that there has been a public sector pay freeze, we’re in pretty tough times.”

The Government has made several U-turns in the past 12 months, notably on the decision to not extend free school meals into the holidays and on a plan to allow households to mix for days over the Christmas period.

Asked on the BBC’s Andrew Marr Show whether he believes nurses deserve more than a 1% pay rise, Education Secretary Gavin Williamson said: “What we are having to deal with is an incredibly challenging economic situation where we have put forward a proposal.

“We’ve put forward what we believe we can afford and is part of a process and that was what will be looked at.

“But really, our focus is on making sure we recover from this pandemic.”

Pressed on whether the planned pay rise could be increased, Mr Williamson added: “We’ve stated that this is very much part of the process – what the Government has put forward has been passed to an independent review.”

Labour’s Jonathan Ashworth said Conservative MPs had already voted for a pay rise of 2.1% for NHS workers.

Holding up some papers on the Andrew Marr Show, the shadow health secretary said: “This document is the NHS long-term spending plan – it promised a 2.1% increase for NHS staff.

“Not only was it promised, it was budgeted for and it was legislated for – this is the law of the land.

“Tory MPs voted for 2.1%.

“The Government budgeted for 2.1% and it was passed in legislation because the spending plans for the NHS came to the House of Commons and it went through the Commons – every Tory MP voted for 2.1% in January last year.

“That should be the basis for which negotiations and discussions are now entered into with the trade unions.”

The Government is facing fresh warnings of a staff “exodus” and a waiting list crisis if it presses ahead with a controversial 1% pay rise for NHS workers.

The Unite union, which has more than 100,000 members in the health service, said a lack of a decent increase will lead to a shortage of professionals to carry out vital operations.

The latest warning came as controversy continues to swirl over the Government’s recommendation of a 1% pay rise to the independent NHS Pay Review Body.

Ministers have been warned of possible industrial action, while the Unison union is calling on the public to join a nationwide “slow handclap” next Thursday evening to show their anger at the Government.

Dr Nikita Kanini, the NHS medical director for primary care, said she is worried that the “incredible” NHS nurses who have “been front and centre of this pandemic” will leave the profession.

She told Times Radio Breakfast they may go “partly because of concerns around pay but partly because of exhaustion” and “so it’s really important that our staff get the support and the recognition they need”.

Unite said anger felt by NHS staff at the “insulting” government proposal would exacerbate an existing serious recruitment and retention crisis in the NHS.

Assistant general secretary Gail Cartmail said: “The NHS will be a pale shadow of the great Covid-fighting health service we know and love in five years’ time, if the insulting 1% pay recommendation is not dramatically revised upwards by ministers.

“NHS staff are exhausted after a year of tireless caring for patients during the pandemic and many are now prepared to leave the health service after a decade of pay austerity which has seen pay packets for many shrink by 19% in real terms.

“The 1% recommendation could be the last straw for many dedicated staff.

“The NHS already has an estimated 100,000 vacancies, including 40,000 nursing posts – and a massive backlog of non-Covid procedures, such as cancer treatments.

“The Tories’ tight-fisted policy on NHS pay since 2010 will have a poisonous sting in the tail in the years to come and lead to an exodus of experienced staff that the NHS can ill-afford to lose.

“The British public needs to speak up now for the NHS and additional investment in services and funding for a significant pay rise.

“Otherwise, in five years’ time, there may not be the staff to see that your granny’s hip replacement is done on time as waiting lists spiral out of control.”

Unite said it is liaising with other health unions about the next steps in the pay campaign, including the possibility of a ballot for industrial action.