UK telecoms firm MMO2 has sold its O2 Netherlands unit to Dutch investment group Greenfield Capital Partners.
The Dutch mobile phone market is very competitive
The Dutch company will be paying 25m euros (£17m) in cash for O2 Netherlands, formerly known as Telfort Mobiel.
MMO2, which was once part of British Telecom, said it would be putting the cash back into its business.
"We believe that this deal is in the best interests of MMO2 shareholders and also represents a good opportunity for the Dutch business, its employees, customers and suppliers going forward," said MMO2 chief executive Peter Erskine.
"The Greenfield offer enabled us to sell at a realistic valuation given market conditions in the Netherlands," he added.
The mobile phone market in the Netherlands is dominated by two players, KPN and UK company Vodafone.
Three smaller players, including O2 Netherlands, are left to fight over the rest of the market share in the highly competitive Dutch mobile phone market.
Greenfield is the owner of Enertel, one of Holland's biggest internet providers.
The sale of the Dutch unit comes after reports that MMO2 and Dutch telecoms giant KPN were in merger talks earlier this month.
O2 Netherlands, which employs 750 people and provides services to some 1.25 million customers, has an annual turnover of £200m.
Operating losses in the year to 31 March were £119m.