VIENNA, June 1 (Reuters) - Mobile phone services piggy-backing on the infrastructure of bigger rivals in Austria are beginning to weigh on prices, which had been rising since a merger reduced the number of network operators from four to three in 2013, according to industry regulator RTR.
All prices were slightly down in the first three months of the year and prices could fall further, the head of RTR, Johannes Gungl, said on Monday.
"I can imagine that we will see a further downwards trend in prices," Gungl told reporters.
Low-usage tariffs fell the most in the quarter, according to the latest data from RTR.
However, average prices have risen by more than 30 percent between late 2013 and the end of 2014 and are still markedly above levels prevailing before Hutchison Whampoa unit Drei Austria bought Orange Austria in January 2013.
To win approval for the deal Hutchison had to agree to make wholesale access to its network available to up to 16 so-called mobile virtual network operators (MVNOs).
But it has taken two years for new MVNOs to start shaking up the market with new mobile offers coming from German retail giant Aldi's Austrian arm Hofer and cable group Liberty Global's UPC Austria.
RTR expects a few more market entries in the months ahead.
Since the Austrian merger the number of network operators in Germany and Ireland has similarly been reduced through consolidation to three from four while in the UK Hutchison's Three is set to buy Spanish group Telefonica's O2 UK.
Telekom Austria, a unit of America Movil , is the market leader in Austria. T-Mobile Austria, a subsidiary of Deutsche Telekom, is ranked as second-biggest, with a market share of around 30 percent. (Reporting By Angelika Gruber; Writing by Shadia Nasralla; Editing by Greg Mahlich)