Any measures to help pupils catch up on lost learning could arrive “too late” if the Government delays announcing new funding until autumn, the Institute for Fiscal Studies (IFS) has warned.

A £15 billion education recovery package over three years could be “a terrific investment” if it helps to mitigate the future lost earnings of schoolchildren, the analysis says.

It came after the education catch-up tsar quit with a stinging condemnation of the Government’s £1.4 billion recovery fund for children who have been affected by school closures due to the pandemic.

Sir Kevan Collins resigned on Wednesday as education recovery commissioner as he warned the support package “falls far short of what is needed” to meet the scale of the challenge.

IFS researchers warned: “If new spending is only announced in the autumn, the actual measures could be delayed well into 2022 – potentially too late to effectively make up for lost learning.”

There are some good arguments for delaying decisions until the autumn spending review, but the risk is then that any measures would arrive too late to help the pupils most in need of support

“If these losses are not properly addressed, then the long-run costs could easily run into the hundreds of billions as a result of lost skills and productivity,” the observation adds.

It has been previously reported that Sir Kevan had called for £15 billion of funding and 100 extra hours of teaching per pupil as part of his recommendations for addressing lost learning.

Sir Kevan also recommended that schools and colleges should be funded for a flexible extension to school time, the equivalent to 30 minutes extra every day.

The Department for Education (DfE) has committed to a review of time spent in school, with findings due later in the year to inform the spending review.

On the additional £1.4 billion of funding for pupils in England – which is on top of the £1.7 billion already pledged for catch-up – the IFS researchers highlighted that the recovery package is smaller than other countries.

The IFS report says: “The fund equates to just over £300 per child in nurseries, schools and colleges, spread over three years (so about £100 per pupil per year, or 1.7% of annual school spending per pupil).

“These figures are well below the £15 billion reportedly recommended by the education recovery commissioner, and much smaller than those being implemented in some other countries (about £1,600 per pupil in the US, and £2,500 per pupil in the Netherlands).”

It added: “£15 billion sounds like a lot of money to spend on education recovery. But spread over three years, it would have averaged about £5 billion per year, or just over 10% of annual spending on schools pre-Covid.

“If it genuinely helped to mitigate the future lost earnings of today’s schoolchildren (which could easily run into the hundreds of billions over the coming decades), it could also prove to be a terrific investment.”

On Wednesday Education Secretary Gavin Williamson sidestepped questions about reports of a row with the Treasury over the funding, but he did admit “there will be more that is required”.

Ben Zaranko, a research economist at the IFS, said: “A one-off injection of education spending could prove to be a fantastic investment if it helps to mitigate losses from disrupted learning in the pandemic.

“From the Treasury’s perspective, the question is whether this programme would truly help to mitigate those losses, and whether it would truly be a one-off.

“There are some good arguments for delaying decisions until the autumn spending review, but the risk is then that any measures would arrive too late to help the pupils most in need of support.”

A Government spokesperson said: “We have committed to an ambitious, long-term education recovery plan, including an investment to date of over £3 billion and a significant expansion of our tutoring programme, to support children and young people to make up for learning lost during the pandemic.”