Anger is mounting after it was revealed Royal Mail chief executive Adam Crozier received more than £3 million in pay, pensions and incentives in the last financial year.
Calls have been made for the company, which is under attack for closing 2,500 post offices, to come under closer scrutiny.
Figures for the 2007/08 financial year showed that Mr Crozier's basic salary remained unchanged at £633,000, but this was increased to £843,000 because of an annual performance bonus and other benefits. He also received £1.99 million for a long-term incentive plan covering three years and a cash supplement in lieu of pension of £208,000, according to the report.
Royal Mail's chairman, Allan Leighton, whose pay and bonus remained at £200,000, said of Mr Crozier's salary: "The payment covers three years during which the group, led by Adam and the team, has consistently exceeded expectations and met all the targets set by the shareholder, and that's against a backdrop of a declining overall mails market, accelerating competition and a pension fund that consumes around £800 million a year in cash."
But Dave Ward, deputy general secretary of the Communication Workers Union, said: "The actions, wages and misjudgements of Royal Mail management demands closer scrutiny. They have got a business plan that is in crisis. They are always shifting the blame and yet they reward themselves with obscene amounts of money."
Mr Ward said Mr Crozier should follow the lead of British Airways boss Willie Walsh who has forgone his bonus.
"Rewarding the misjudgements of executives like this is a public scandal that they should not be allowed to get away with."
Paul Reuter, national officer of Unite, said: "This is immoral. They are rewarding themselves fantastically for failure. This comes at a time when they are cutting jobs and pensions and closing post offices."
The annual report also revealed that Ian Griffiths, who left his job as managing director of the letters business last year after being in the job for around a year, received £500,000 as compensation for loss of office.
Shadow business secretary Alan Duncan said: "A proper reward is one thing but I cannot see the performance that justifies these massive figures. It does seem highly excessive. I can't see he's worth 10 times the Prime Minister, not even this one!"
