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May 5 (Reuters) - Danish telecoms operator TDC posted better-than-expected first-quarter results on Friday, lifting its shares, though the firm also warned that new regulations to end roaming charges in the European Union will be a challenge.
* Roaming charges in the European Union will end as of June when Europeans will no longer have to pay a fee to use their phones when they travel in the bloc.
* The big question for 2017 is how the consumers will use their mobile phones while travelling after the roaming charges have come to an end, chief financial officer Stig Pastwa told Reuters in a telephone interview.
* "If all users max out on data it'll be very expensive since we would have to buy space on some of the other distributors' networks," Pastwa said.
* He said the new roaming regulations could cost TDC around 150 million Danish crowns ($22.11 million) and that the company had hiked monthly payments for mobile phone subscriptions by 10 to 20 crowns to counter that impact
* In February, Vodafone chief executive Vittorio Colao said the European Commision should help telecom firms by cutting spectrum costs and allowing more mergers to help offset the loss of revenue from ending roaming charges.
* TDC reaffirmed its guidance for 2017 of an EBITDA of more than 8.2 billion Danish crowns, stable or moderate growth in equity free cash flow and a dividend per share of 1.05 Danish crowns.
* First-quarter revenue came in at 5.21 billion crowns beating the expectations by analysts polled by Reuters of 5.12 billion Danish Crowns.
* First-quarter EBITDA came in at 2.13 billion crowns beating the 2.08 billion expected in the poll.
* At 1055 GMT, TDC shares traded 3.5 pct higher for the day Source text for Eikon: Further company coverage: ($1 = 6.7828 Danish crowns) (Reporting by Julie Astrid Thomsen, editing by Teis Jensen and Terje Solsvik)