The postal workers' union has described the share sale of Royal Mail as a "debacle".
Stocks in the company have almost doubled in value since they went on sale and the Communication Workers Union (CWU) has called for the government to halt payments to the banks that advised on its valuation.
The CWU's general secretary, Billy Hayes, stated that hundreds of thousands of pounds worth of taxpayers' money has been lost as a result of Royal Mail being undervalued.
Stocks in the firm went on sale at 330p but have since risen to nearly 600p, resulting in major gains for those who invested in the company.
Mr Hayes said: "At the very least the institutions which advised the government should not receive any further payments, which are discretionary."
He added that the government ought to also think about claiming back fees paid for "shoddy advice" that has cost the taxpayer money.
The share price of Royal Mail is slightly down in early trading this morning (November 21st). At 08:19 GMT, its stocks were down 0.74 per cent for the day.
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