The Dutch consumers’ authority ACM has cleared the main Dutch mobile phone operators of cartel-forming and price-fixing after a two year investigation.

However, the ACM did warn phone firms that ‘public statements about future market behaviour could carry antitrust risks’. These include statements made in public about planned price increases or changes in conditions which have not been finally agreed, the organisation said.

‘If competitors took note and followed such publicly-made statements, it could lead to collusive behaviour, which is harmful to consumers,’ the ACM said.

The three major mobile providers in the Netherlands – KPN, T-Mobile and Vodafone – have all agreed to comply with this.

The investigation followed allegations made by two whistleblowers in late 2011 and concerns about the way all three companies introduced more expensive subscriptions for smart phone users within a short space of time.