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(Adds European Commission, Orange decline to comment, Jazztelshares)
By Foo Yun Chee and Julien Toyer
BRUSSELS/MADRID, Dec 3 (Reuters) - EU antitrust regulatorsare likely to expand their scrutiny of Orange's 3.4-billion-euro ($4.2 billion) bid for Jazztel,stepping up pressure on the companies to enhance theirconcessions, two sources familiar with the matter said onWednesday.
Orange, France's largest mobile firm, is looking to use thedeal to get ahead of rival Vodafone in the Spanishmobile market. Telefonica is the market leader there.
The companies offered concessions to the European Commissionon Nov. 13. The sources said the EU competition watchdog did notconsider these sufficient.
One of the sources said the Commission was likely toannounce the opening of an in-depth investigation on Thursdayand also reject a request from the Spanish competition authorityto examine the case.
Commission spokesman Ricardo Cardoso, Orange and Jazzteldeclined to comment. The deadline for the Commission'spreliminary review is Thursday, Dec. 4. An in-depth probe takesup to 90 working days and can be extended to 105 working days.
Jazztel shares were down 0.8 pct at 12.57 euros at 1515 GMT,the biggest loser in Spain's blue-chip index Ibex which was up1.26 pct.
The acquisition of Jazztel would add 1.5 million broadbandsubscribers to Orange's client base and also help it take oncompetitors with fixed, TV and wireless packages.
The Spanish telecoms market has seen a wave of consolidationin recent months as tough competition and falling prices hitoperators. The most notable deal was Vodafone's 7.2-billion-eurotakeover of Spanish cable operator Ono in March.
(1 US dollar = 0.8119 euro) (Additional reporting by Gwénaëlle Barzic in Paris; editing byJulia Fioretti/Keith Weir)
