Vodafone could be interested in buying Spain's fourth-largest mobile operator Yoigo once it is clear how tough the European regulator will be on tie-ups in the sector, the firm's chief executive said.
Takeovers in Europe's telecoms sector - facing its fifth year of declining revenues - could be held back if regulators demand strict concessions in return for approving deals.
Yoigo, owned by Sweden's Teliasonera, has been a potential bid target for some time, with France's Orange and Spain's Telefonica also considered possible buyers.
"We are obliged to look at everything, although for something like Yoigo we would need the European Commission to make its stance clear on current consolidation deals," Vodafone's CEO Vittorio Colao said in Madrid.

Market players are waiting for the European Union to decide on Telefonica's proposed €8.6 billion takeover of KPN's E-Plus unit in Germany to see if the regulator demands concessions in return for approval. A decision is due by June 23.
Rivals such as German telecoms and Internet services provider Freenet and United Internet say Telefonica should be forced to give competitors cost price access to its German network and sell some of its prepaid brands.
Vodafone last month agreed to buy Spain's largest cable operator Ono for €7.2 billion in a move aimed at creating a stronger challenger to market leader Telefonica.
Speaking after the publication of first-quarter results earlier today, Teliasonera CEO Johan Dennelind said the firm would need to consider other options for Yoigo if it could not reach a sustainable size in Spain through organic growth.