Experts all agree NHS needs more money, Boris Johnson tells May

Boris Johnson will tell cabinet colleagues that all experts are agreed on the need for an urgent financial boost for the NHS, as he warns that Conservative failure to act will result in Jeremy Corbyn winning the next election.

Allies of the foreign secretary suggested that he would not stop making the argument for more money – with a particular demand for £100m extra per week after Brexit – until Theresa May concedes.

They insisted the pressure was not simply about fulfilling the pledges painted on the side of the Vote Leave campaign bus. They said Johnson believed the issue was at the top of voters’ concerns and suggested he was frustrated that key advisers to the prime minister had indicated the Tories were too far behind Labour on the issue to make it worth an intense policy focus.

“Boris believes that if the Tories are going to beat Corbyn at the next election they must make the NHS a top priority and deliver new funding,” said an ally. “Every poll conducted shows the NHS is top of swing voter concerns and every expert says it needs more money. The cabinet will have to act and the sooner the better.

“This isn’t about the referendum, it’s about delivering on the number one concern for the public and beating Corbyn at the next election.”

The foreign secretary is said to be frustrated by a suggestion from May’s chief of staff, Gavin Barwell, that the NHS is not necessarily a sensible target for Tories because they cannot catch up with Labour on the issue. That led to a decision from inside Downing Street to focus most heavily on school standards, the environment and housing towards the end of 2017. However, since then the NHS appears to have been added to the list.

Speaking at the start of a year in which the Tories face a challenge in London council elections, the friend stressed Johnson’s past success in the capital. “Boris has a track record of winning and knows the Tories simply cannot afford to concede the NHS to Labour, which is why he will continue to make this argument until it happens.”

Johnson will make the argument during a cabinet meeting on Tuesday where ministers will get an update on winter pressures facing the NHS. He hopes to attract the support of the key Brexiters Michael Gove, Chris Grayling and Penny Mordaunt, as well as the health secretary, Jeremy Hunt.

His decision to cite expert opinion could raise eyebrows among cabinet colleagues who campaigned to remain in the EU. During the campaign, Johnson’s leave campaign partner Michael Gove suggested Britain had had enough of the arguments of specialists.

Labour has been ramping up pressure on the government over failures in hospitals, with Corbyn and the shadow health secretary, Jonathan Ashworth, holding a rally this week demanding an emergency budget for the NHS.

Ashworth addressed Labour MPs at a meeting of the parliamentary Labour party on Monday, and was due to say: “The toxic privatisation agenda in our NHS has gone too far. Billions of pounds has flowed out of the NHS into private sector hands leaving a poorer service for patients.”

Johnson has been gearing up to press May for more funding for the NHS since he repeatedly promised that Brexit would deliver a financial dividend for the health service. Last week the foreign secretary angered opponents suspicious of his £350m figure by claiming it was an underestimate and that Vote Leave could have opted for a higher £438m a week.

However, he has conceded that the figure used by his campaign was a gross one, and now says that £100m should be spent on the NHS.

A Downing Street source suggested May had made clear that the NHS was a priority. “Look at the budget: the NHS got a significant amount of money and although outcomes are improving we want to ensure that progress is secured for the future,” the source said.

The NHS England chief executive, Simon Stevens, has made clear there is not enough money to fund everything being asked of the health service. And Sir Malcolm Grant, the chairman of NHS England, said at a board meeting: “We should not set out blindly imagining that our staff can do everything. There are going to have to be tough decisions and trade-offs.”