The dispute between the main postal union and Royal Mail worsened yesterday after the postal group warned that it would not increase a pay offer despite a vote by postal workers for strike action.

The Communication Workers Union accused Royal Mail of deliberately attempting to undermine the union rather than negotiate to avert the first national strike for 11 years.

Its comments came after Allan Leighton, Royal Mail’s chairman, and Adam Crozier, its chief executive, wrote to the CWU warning that there would be no change to the offer and claiming that most postal workers did not want to go on strike.

The letter was sent on Friday, the day after postal workers voted by 77 per cent in favour of strike action.

Royal Mail has offered a 2.5 per cent pay rise, while the union is seeking a 27 per cent increase over five years to bring pay in line with the national average. The two sides are also at odds over the company’s business plan, which involves £380 million of cost-cutting this year.

The union’s postal executive will meet today to set out its strategy in the dispute. It is unlikely to set strike dates yet, to allow Royal Mail more time to make a revised offer. Legally, the union has 28 days from last Thursday to set a date for any strike action.

Dave Ward, deputy general secretary of the CWU, said: “Royal Mail leaders are in denial about the yes vote and the fact that an overwhelming majority of their workforce have rejected their business plan.”

He accused Royal Mail of being confrontational and of attempting to undermine the union, saying: “If that attitude continues then a strike is inevitable.”

The letter from Mr Leighton and Mr Crozier says of postal workers: “Many believe that, given our current financial position, the pay offer is acceptable; some are fearful of change; some are disappointed they have not had the opportunity to vote on the package of pay and change; and nearly all of them are telling us that they do not want to go on strike.”

A spokesman for Royal Mail said that the group was available to explain the current offer, but that there could be no more money on the table.

The CWU must give a week’s notice of strike action. Royal Mail is preparing for some managers to deliver mail. However, this can only cover a small amount of the market.

A strike would involve more than 130,000 workers across delivery, post office counters and the cash handling service.

Business groups have warned that a strike would be very damaging to small business, which relies on receiving cheques and sending invoices frequently. Business has also warned that companies will seek other forms of communication to mail and may not return to it once the dispute is over.

The last national strike, in 1996, lasted several weeks. A current dispute is likely to be fought with a series of short, sharp shocks in one-day walk-outs.

It is likely that the strikes could be staged on a Friday and the following Monday for maximum effect.

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