AN expected £20 billion cash boost for the NHS in England would provide the Scottish Government with a near £2bn knock-on windfall, which would also likely be spent on improving health care services north of the border.

The suggestion that Theresa May - under growing pressure to increase health spending - will next week announce a multi-year settlement ahead of the 70th anniversary of the NHS in July, came as a poll showed 66 per cent of voters - including 63 per cent of Conservatives - would be willing to pay 1p more on their income tax to provide a funding boost for the NHS.

The YouGov survey for pressure group 38 Degrees found that 73 per cent of those asked did not believe politicians were prepared to make difficult decisions about how to fund the NHS.

But it also said 66 per cent of respondents said they would be ready to pay an additional one per cent in income tax to pay for the NHS.

This could raise £5.5bn a year for health in England and Wales, according to a report by the Centre for Economics and Business Research launched by 38 Degrees.

David Babbs, the Executive Director of the pressure group, said: "The Government knows the NHS needs more sustainable funding but the last few days proves they haven't worked out how.

"They now have a clear mandate from the British people, who are willing to pay a bit more in income tax to give our NHS the proper funding boost it needs - not a sticking plaster solution."

It is suggested that the Prime Minister will announce a cash injection of up to £5bn a year for four years as early as Monday. The cash boost will be funded by a mixture of borrowing, income tax and a hoped-for "Brexit dividend" from leaving the EU.

Such a move would mean, under the Barnett Formula, the Scottish Government would receive a proportionate nine per cent share based on Scotland’s population; £450m a year or £1.8bn over four years.

While any knock-on windfall would be up to Scottish Government Ministers to decide what to spend the money on, there would be enormous pressure for them to follow suit and spend it on NHS Scotland.

Downing Street declined to comment on reports that ministers were considering raising some of the cash by freezing the thresholds for the standard and higher rate of income tax from April 2020.

But No 10 pointed out how the Government had always said that when Britain left the EU, it would not being paying billions of pounds a year into EU coffers and that some of that money could be spent on priority areas, including the NHS.

A report by former health ministers Lord Darzi and Lord Prior argued the case for guaranteeing growth of around 3.5 per cent a year in health spending over the long-term in order to ensure the NHS was fully funded.