The Dutch parliament is moving ahead with plans to investigate the country's mobile phone licence auction in July.

Their concern is that it raised much less than expected.

In an advertisement placed in Staatscourant - the official state publication for announcements and legislation - on Wednesday the parliament invited independent investigators to tender for carrying out the probe.

The investigation should result in a number of lessons for the future

Dutch parliament

The parliament had hoped the auction for third-generation licences would generate about 20bn guilders ($8bn) in windfall revenue for the government, following the success of similar licence auctions in the UK and Germany.

But it raised only 5.9bn guilders while, amid allegations of collusion and threatening behaviour among bidders, the five licences on offer went to the five existing Dutch mobile network operators.

Pushing up the prices

The parliament now wants to know precisely how the auction was run, how this compared with other European auctions and whether the method might be improved for any future auctions in the Netherlands.

"Ultimately the investigation should result in a number of lessons for the future and provide, among other things, recommendations for the planning of subsequent issue of licences," the advertisement said.

The licence winners

KPN Telecom Vodafone-backed Libertel Dutchtone BT's Telfort Ben

The attention of the probe will focus on the government's behaviour, while the conduct of the bidders is being separately investigated by the Dutch competition watchdog.

It is looking into claims by broadband firm Versatel that British Telecom's Telfort - one of the successful bidders - had pressured it to exit the bidding on grounds that Versatel could not afford a licence and was only pushing up the prices for others by staying in.

Parliament set a bid deadline of 8 January for prospective investigators and said it wanted the probe to get underway in February and be completed within three months.