The communications regulator (ComReg) will review the quality of service targets that it sets An Post after finding that successive price rises had not improved its quality of service.

The review will focus on ordinary letters that individuals and businesses post on a daily basis, which represents about 51 per cent of An Post's revenues.

ComReg chairman, Mr John Doherty, said yesterday that quality targets set by ComReg had not been met by the firm. "Prices have increased substantially over the last two years but there has been no discernable improvement in quality," he added.

An Post is specifically being asked to explain why it has not been possible to provide a next-day delivery for a greater proportion of letters. The review will ask the firm to quantify what factors have impacted on deliveries.

It will also ask customers to set targets that they deem appropriate for An Post to provide. ComReg said this target must be consistent with the objective of providing next- day delivery - while allowing for "exceptional factors" and "unforeseeable circumstances."

An Post, which is in the middle of major financial restructuring, said providing a higher quality service would cost a lot more to implement. This was not recognised in the document, said an An Post spokeswoman.