By Ian Dunt
The Royal Mail strike will begin at midnight tonight after talks broke down between postal workers' leaders and management.
The two sides have been in talks for around 30 hours this week but tempers on both sides appear to have prevented an end to the strike.
The strike will last for two days, but the backlog means the system will take far longer to recover.
A Communications Workers Union (CWU) official told journalists today: "The real truth behind this dispute is that Lord Mandelson clearly feels it's payback time because we defeated them on their proposal on privatisation."
Lord Mandelson, who officials described as "secretary without responsibility", was accused of working "hand in hand with Royal Mail" to derail the talks.
The row centres on efficiency measures demanded by management - branded 'modernisation' by both Royal Mail and business secretary Peter Mandelson, who launched an attack on the strike in the Lords yesterday.
He reiterated the thrust of his argument today, saying: "I deeply regret this decision. National strike action is not in the best interests of the company, the workforce or the hard-pressed consumers and businesses that depend on Royal Mail."
Gordon Brown was challenged on the issue today during prime minister's questions as David Cameron blamed his "weakness" for increasing union militancy.
A bill to part-privatise the Royal Mail had been due to go before the Commons earlier this year but an extensive campaign by Labour backbenchers forced the government to back down.