BRUSSELS, Oct 1 (Reuters) - Belgian mobile phone operators BASE and Mobistar SA have filed a complaint with European antitrust regulators alleging Belgacom SA abused its dominant position in its home market.
The joint complaint -- filed in April but not previously publicly revealed -- argued former state monopoly Belgacom abuses its position in the Belgium broadband Internet market.
"Although Belgacom has offered us access to its ADSL2+ and VDSL2 (fast Internet) networks, we feel that the conditions are not fulfilled to allow for sufficient competition," a spokeswoman for Mobistar said on Thursday.
Mobistar, majority owned by France Telecom SA, is Belgium's second-biggest mobile phone operator and also provides broadband services.
BASE, owned by Dutch telecoms operator Royal KPN NV, is Belgium's third and smallest mobile operator and is active in broadband through Tele2 Belgium, which KPN acquired in 2007.
"Belgacom has also caused us a number of operational difficulties, for example when customers decide to move from Belgacom to us," a spokesman for BASE said.
But Belgacom said the operators had no grounds for complaint. "They have access to our network. These are regulated prices which were approved by (Belgian telecoms regulator) BIPT," a spokeswoman said.
Earlier this week, antitrust prosecutors advising Belgium's competition watchdog said Belgacom had engaged in a "margin squeeze" aimed at driving out competition.
In May, the competition authority imposed a 66.3 million euro ($96.6 million) fine on Belgacom's mobile arm Proximus after a complaint filed by BASE in 2005.
"We are counting on the fact that things will move forward faster in Europe than in Belgium," BASE's spokesman said. (Reporting by Antonia van de Velde; Editing by David Holmes) ($1=.6863 Euro)