Postal workers are to be balloted over their first industrial action for seven years.

Around 160,000 members of the Communication Workers Union will vote on whether to hold a series of national strikes over this year's pay offer.

Union leaders say that Royal Mail's offer of a 14.5 per cent rise over 18 months is a "dishonest" claim, and that there were only definite increases on the table of three per cent from October and 1.5 per cent from next April.

There is also a dispute over the "strings" attached to the deal.

"The Royal Mail is being dishonest by claiming they are offering 14.5 per cent," said deputy general secretary Dave Ward.

"If that was the case, the union would be biting their hand off."

However, the company argues that the deal is worth 14.5 per cent on pensionable pay, linked only to "simple" changes to improve productivity.

A spokesman said the latest deal contained less clauses than the one recommended for acceptance by the CWU earlier this year.

He also pointed out that Royal Mail continues to lose £750,000 per day.

The watchdog for the postal service, Postwatch, also highlighted the change from a six-day working week to five days also included in the package.

"If employees vote for strike action, it will be the consumers that lose out," warned chairman Peter Carr.