Sir Keir Starmer has said NHS workers should get a “fair” pay rise, but declined to back a 12.5% increase proposed by the Royal College of Nursing.

Launching his campaign for May’s elections, the Labour leader targeted the Government’s widely criticised recommendation of a 1% raise for England’s health workers.

He said on Friday that “a vote for Labour is a vote to support our nurses”, but did not go as far as some supporters wanted in specifying the raise they deserve during the pandemic.

Asked at the virtual launch, Sir Keir said the increase should be “above inflation, a real rise”.

“I think the starting point should be the 2.1% that was promised and was, of course, budgeted for,” he added.

Sir Keir did not directly answer questions about his support for potential strikes by nurses, saying it is in the hands of Boris Johnson to prevent industrial action.

“I support them in their entitlement to a fair wage rise after what they’ve been through. They don’t want to go on strike, it’s the Prime Minister that’s causing this dispute and it’s the Prime Minister that can sort it out,” Sir Keir said.

Momentum, the campaign group that championed Jeremy Corbyn, earlier criticised the party leadership and said they must “stand up for working people” after Sir Keir’s deputy, Angela Rayner, appeared not to back the nursing union’s call for a 12.5% raise.

Sir Keir drew on his mother and sister having been nurses, and his wife working for the NHS, in trying to maintain focus on the pay row.

“When I clapped for our carers, I meant it,” he said. “The Prime Minister clapped for carers, then he slammed the door on them.”

Meanwhile, Chancellor Rishi Sunak continued the Government’s defence of the proposed raise, arguing it was “proportionate, fair and reasonable”.

He told the Commons Treasury Committee he had set out a “targeted approach” to public sector pay in last year’s spending review.

Sir Keir, who has been struggling to overturn the Tories’ popularity after taking over the Labour leadership, acknowledged it was a “tough environment” to campaign during the pandemic.

“They are going to be really tough elections, we’re in the middle of the pandemic and we’ve been constrained. I’ve yet to make a speech to a live audience,” he said, as he declined to say what success would look like for Labour.

Sir Keir criticised the Conservatives for “tax rises on families” after they froze income tax thresholds, and accused the party of failing to fix social care.

He stressed “this is a different Labour Party, under new leadership” in attempting to highlight the distance between himself and Mr Corbyn, who led the party to a dismal general election defeat in 2019.

Mr Johnson has argued he has tried to give NHS staff “as much as we possibly can”, but the policy is seen as deeply unpopular with voters.

With threats of industrial action and demonstrations planned across England, a poll at the weekend suggested 72% of the population thought the rise is too low, including 58% of Tory voters.

However, polling has also highlighted the struggle Sir Keir is facing, with national voting intentions consistently putting the Conservatives ahead of Labour.

Voting on May 6 will include polls for district and county councils in England, police and crime commissioners and city mayors, including in London.

With Scottish Parliament and Welsh Assembly elections also taking place, Sir Keir criticised Nicola Sturgeon’s SNP for “fighting among themselves rather than fighting for the Scottish people”.

Campaigning during the pandemic will look different, with doorstep activism under Covid-secure guidelines and voters being asked to take their own pens to the polls.