Image copyright Getty Images Image caption The Postcode Address File contains all known UK delivery addresses

The inclusion of a valuable database of postcodes and addresses in the Royal Mail flotation has been criticised by an influential group of MPs.

The Public Administration Committee said the Postcode Address File (PAF) was a national asset and should not have been included in privatisation.

It includes all known postal addresses in the UK, with 1.8 million postcodes.

The committee's report said the PAF was included to boost Royal Mail's value but this was denied by the government.

'Never again'

The MPs said the database had been expensive to collect and was of "huge direct value" to the economy.

The PAF, a complete set of the nation's postcodes, is valuable because its details can be used by businesses for mailshots and marketing.

What is the Postcode Address File? The PAF is a database of mail delivery points

Names of private individuals are not included, except when it is the only way of identifying a delivery point

It contains 29 million business and residential addresses to which mail can be delivered

There are 1.8 million UK postcodes and 1.4 million business names

It covers England, Scotland, Wales, Northern Ireland, Jersey, Guernsey and the Isle of Man Source: Royal Mail

The committee expressed concern about the credibility of assurances over continued access for small businesses and others, now the database was in private hands.

Committee chairman Bernard Jenkin said: "The sale of the PAF with the Royal Mail was a mistake. Public access to public sector data must never be sold or given away again.

"This type of information, like census information and many other data sets, is very expensive to collect and collate into useable form, but it also has huge potential value to the economy and society as a whole if it is kept as an open, public good.

"The UK government was an early mover on government open data, but other governments, watching the UK with interest, are catching up fast.

"If the government does not take the opportunities offered, there is a risk in the UK that businesses with growth potential will be deterred by fees for data, and by legal and administrative barriers, while other countries are developing their data industrial base and stealing a lead over the UK."

'Integral part'

The committee said making public data available could empower people, make government more accountable, improve public services and benefit the economy and society as a whole.

Analysts Deloitte had assessed the value of this information to consumers, businesses and the public sector at £1.8bn a year, it added.

The government said it had ensured the postal database remained available for some other uses, including a free option for looking up postcodes.

A spokesman for the Department for Business, Innovation and Skills said: "The Postcode Address File was included in the sale of Royal Mail because it is an integral part of its operations, not to boost the price."

Royal Mail said it was working on a proposal to widen access to the PAF.

"Royal Mail recognises the importance that PAF plays as a vital dataset supporting and sustaining key parts of the UK economy and we are committed to its widespread availability at a fair price," it said in a statement.

Labour trade and investment spokesman Ian Murray said: "This report raises yet more concerns that taxpayers have been short-changed by David Cameron's botched Royal Mail fire sale, losing valuable public assets including the Postcode Address File to City speculators."