The country's should force Telefonica to share the fibre optic network it is rolling out in Spain, according to Vodafone.
A Dow Jones report further quoted Vodafone Spain CEO Francisco Roman saying that 'the regulator's decisions don't address the lack of viability of laying two separate fibre optic networks.'
The executive also said an operator needs a market share of at least 40% to justify its own fibre roll out. Telefonica has a 64% market share of traditional fixed line Internet subscribers, while Vodafone's recently acquired operator has a 3% market share.
Cable operator Ono and France Telecom's Orange each have roughly a 10% share, and the rest is divided among smaller operators.
Last month, the telecoms watchdog decided Telefonica would have to allow competitors to lay cable in its underground cable ducts, but wouldn't have to share the fibre optic lines, the Dow Jones report said.
Telefonica is the only Spanish operator with its own fixed line network and currently acts as a wholesaler so other operators can offer voice and Internet services over its fixed line network.
Roman added the new regulation strengthens Telefonica's grip on the market and undermines competition, hurting consumers.