Royal Mail Group is expected to reveal a £10 billion deficit for its defined benefit (DB) pension fund.
Adam Crozier, Royal Mail chief executive, said the pension fund deficit was currently being revalued, but the historic deficit was expected to reach at least £10 billion, compared with £3.4bn in the last valuation three years ago.
In the first half of the financial year 2009/2010, Royal Mail Group made a cash payment of more than £300 million into the pension fund.
Dave Ward, deputy general secretary at the Communications Workers Union, said: "We are daunted by the size of the deficit. The government must take responsibility for the deficit, which will allow the company to continue with a modernisation programme which increases profits, quality of service and greater innovation in products and services."
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