A dozen “priority” shareholders raked in millions of pounds of easy profits within weeks of Royal Mail’s flotation by privatisation-obsessed ministers, official auditors revealed yesterday.

A National Audit Office report into the postal fire-sale showed that 16 “priority” investors thought vital to the stability of the company snapped up their enhanced stake on the cheap before making a packet on rocketing share prices.

Twelve of the “priority shareholders” had sold all or some of their holdings within the first few weeks of trading.

On the first day of trading, shares closed at 455p — 38 per cent higher than their sale price and bringing in a £750 million increase for the shareholders — and have since gone for as much as 615p.

Despite requests from the Star, the NAO would not release the identities of the priority investors.

Unions and opposition leaders reacted with fury to the news, with Unite national officer Brian Scott accusing the government of “selling off the country’s family silver on the cheap.”

Postal union CWU general secretary Billy Hayes said the government was in cahoots with the profiteers because of a shared ideology.

He said: “It was never about establishing a long-term shareholder base and all about making a quick buck for City investors.

“This further supports the view that the government was desperate to get rid of Royal Mail because it fitted with their agenda.

“The sell-off was never about getting the best deal for taxpayers.

“The report reinforces that this was a fire-sale package created for political purposes which is simply not good enough and continues to put the future of Royal Mail at risk.”

The NAO also accused the government of selling off more than it needed to for its stated objective of privatisation — the result costing the taxpayer millions.

The government could have retained 110 million more shares, worth £363 million, at the offer price while still privatising the business, said the report.

The government only kept hold of 30 per cent of Royal Mail shares.

Business Secretary Vince Cable defended the findings by blustering that the government had achieved what it set out to do — secure the future of the universal delivery service.

But shadow business secretary Chuka Umunna pointed to a 30 per cent increase in stamp prices and said Mr Cable could not “duck responsibility for what has happened.”