SNP ministers have been accused of spending an “eye-watering amount of money” on consultants – after it was revealed more than £25 million has been paid out to just four companies over the last five years.

Scottish Labour has warned that “serious questions” need to be answered over whether the bill is an appropriate use of public funding.

The figures have been revealed in response to a Freedom of Information request, which lays out how much public money has been spent on big name firms over the last financial year.

Consultant fees from the Scottish Government have soared each of the last five years - with the 2020/21 bill ten times the costs tallied up in 2016/17.

In 2016/17, the Scottish Government spent £1.3 million of public money on big name consultancy firms, with £2 million paid out in 2017/18 and £3.2 million in 2018/19. In the space of a year, the fees for the big consultancy firms more than doubled to £7.5 million in 2019/20 and increased again to £10.7 million last year.

The findings show that Deloitte received a total of £15.7 million over the last five years including £5.4 million last year for developing systems for Social Security Scotland and £1.3 million for the same project in 2019/20.

The firm also received £1.9 million in 2019/20 and £800,000 last year in relation to the Scottish National Investment Bank.

Deloitte has also been handed almost £3 million of public funding on innovation and industries projects.

Ernst and Young has received £5.4 million since 2016/17 including more than £1.5 million for internal audit services and almost £2.5 million classed as energy.

The company has also been given more than £168,000 of public money on “fuel poverty and energy efficiency” costs.

Price Waterhouse Coppers (PwC), which was also handed a £100,000 contract relating to setting up a National Care Service last month, has also received £1.8 million of public funding for consultancy costs over the last five years.

The firm was given more than £630,000 for innovation and industries services and £426,000 last year for ”other health services”.

PwC was also given almost £120,000 in relation to the crisis-hit Ferguson Marine over the last two years and has received £218,000 for “economic policy and advice” services.

Grant Thornton was given £1.9 million of public funding, including more than £1.3 million on energy projects.

KPMG has received almost £28,000 of money for the Scottish Government’s “digital strategy” in 2016/17.

Scottish Labour’s finance spokesperson, Daniel Johnson, said: "This is an eye-watering amount of money being paid to consultancy firms.

"Serious questions need to be asked about whether this is an appropriate use of public money.

"We need to make sure that public money is being spent in the most prudent and efficient way possible, with only those with clear expertise engaged."

Union leaders, who previously warned about PwC's National Care Service contract, have warned over a continuing trend of outsourcing projects away from civil servants.

STUC general secretary Roz Foyer said: “We have previously raised concerns at the use of such consultancy companies rather than the expertise of Scotland’’s civil service.

"Many of the companies listed have a direct interest in the private provision of public services and are hardly banner carriers for the kind of policies we need to rebalance power and wealth in favour of working people and the communities they live in.”

The Scottish Government said the year on year increases in spending was “driven by additional investment in key strategic priorities, including programmes to support innovation and industries, tackle fuel poverty and improve energy efficiency, establish the Scottish National Investment Bank and Social Security Scotland”.

A Scottish Government spokesperson said: "The Scottish Government uses consultancy firms where necessary to undertake work that requires specialist expertise.

"Consultancy spend is rigorously monitored and audited.”