UK taxpayers must brace themselves for another “20 years of hard choices”, according to the head of the Institute for Fiscal Studies.

The director of the politically neutral think-tank, Paul Johnson, said that politicians needed to be honest about the fact that there will have to be long-term tax hikes.

The pledge from the Government to boost NHS spending by £20bn in the next few years will have to come from taxation as relying on long-term borrowing would not be sustainable for government finances, he said.

Tax rises would have to be brought in over the next two decades and services restricted unless economic growth and productivity levels pick up considerably.

Taxes are only slightly bigger than they have been historically, but the share of national income spent on the NHS has risen a great deal.