The Royal Mail privatisation rip-off scandal escalated yesterday when Business Secretary Vince Cable belatedly revealed the bloated financial hawks given the chance to make super profits.

But the beleaguered Lib Dem refused to reveal which of the 16 were the “dirty dozen” investors who sold off some or all of their stake in the first few weeks of trading to make millions.

Among the favoured big investors — supposed to set up a long-term shareholder base for the privatised Mail — was Lazard Brothers, which advised the government on the share sale and then scooped up a juicy chunk of stocks for its asset management business.

Lazard’s international investment banking chairman is Lord Mandelson, the multimillionaire arch-Blairite who tried to push the last Labour government into privatising Royal Mail.

Another big winner was Lansdowne, a hedge fund which has donated large sums to the Conservative Party.

Only 24 hours earlier, Mr Cable had refused to reveal the list of major “pilot” investors, but he was forced to relent yesterday amid a growing storm at Westminster.

During noisy Commons exchanges, Labour leader Ed Miliband declared: “Everything about this privatisation stinks.”

Taxpayers had been ripped-off, and shares which were sold at a knock-down price of £1.7 billion were now worth £2.7 billion, said Mr Miliband.

“The more we know about this privatisation, the bigger fiasco it is.”

Labour MPs and even some Tories complained bitterly that six of the favoured big investors quickly sold off all their shares to make profits totalling hundreds of millions.

Mr Miliband tackled Prime Minister David Cameron after the Lazard Brothers chief executive said there had been an advanced “understanding” with ministers.

The Labour leader complained that selected big investors had been given “a golden ticket” to buy shares, and then sold them off immediately after privatisation.

Amid shouts of derision, Mr Cameron insisted: “There was no agreement.”

Among the big bonanza investors revealed by Mr Cable yesterday were US-based hedge fund Och-Ziff, the Abu Dhabi Investment Authority and the Kuwait Investment Office.