* Iliad bid $15 bln for 56.6 pct of T-Mobile US at $33/share
* BNP, HSBC agree to lend up to $13 billion - sources
* Iliad shares fall as analysts question wisdom, cost of bid
* Shares in French rivals fall as consolidation hopes fade
* Sprint has head start, higher offer for T-Mobile (Adds investor comments, updates shares)
By Leila Abboud and Arno Schuetze
PARIS/FRANKFURT, Aug 1 (Reuters) - Telecoms group Iliad haslined up BNP Paribas and HSBC to finance its bid for T-MobileUS, people familiar with the matter said, as it pursues a dealthat could overturn expectations of industry consolidation inboth the United States and France.
Shares in Paris-based Iliad dropped as much as 13percent on Friday, as analysts questioned the wisdom and cost ofits surprise $15 billion offer for 56.6 percent of T-Mobile US, the No.4 U.S. mobile operator.
Shares in rival French companies Bouygues andOrange also fell on speculation that Iliad's interestin a U.S. deal meant it might not seek a tie-up at home thatcould ease competition in a cut-throat market.
"The offer may even not be meant absolutely seriously," saidFrank Heise, fund manager at Metzler Asset Management and an owner of Iliad shares. "Iliad wants to exert pressure on theplayers in France. It wants to show Orange and Bouygues that itcan go it alone and does not necessarily need them."
In the United States, Iliad is also jeopardising an expectedconsolidation and faces a potential bidding war for T-Mobile USwith No.3 operator Sprint, and its Japanese backerSoftbank.
Iliad, which is being advised by Lazard banker Vincent LeStradic on its offer, said on Thursday there could be nocertainty its bid for T-Mobile US, 66.7 percent owned byDeutsche Telekom, would be accepted.
Sprint and Softbank have been in talks with T-Mobile formonths and agreed in June to a framework of a deal that valuesthe company at roughly $40 per share, sources earlier toldReuters.
Iliad's offer represents a lower price of $33 per T-Mobileshare, and $36.20 if the buyer delivers on $10 billion ofpromised costs savings it thinks it can generate from runningthe carrier more efficiently.
But Iliad, which is majority owned by billionaire founderXavier Niel, believes its bid faces fewer antitrust issues thanSprint's, so Niel thinks he has an advantage in the talks,sources close to the matter said.
The Paris-based broadband and mobile provider said onThursday its bid would be financed in debt and equity.
HSBC and BNP have committed to lending upto $13 billion to Iliad, said one person familiar with thesituation. HSBC is also acting as Iliad's adviser.
Niel would put in up to 1 billion euros of his own money,said the person, and a share sale to raise up to 2 billion euroswould be done at the Iliad level.
Debt would be raised by Iliad, at the level of a 100 percentowned holding company below Iliad, as well as by T-Mobile US.
"Debt will be raised at three levels overall. The deal willstand or fall on the financing," said the person.
"Can Xavier Niel pull it together? It's a very largeleveraged deal. It has a lot of similarities to Numericable'ssuccessful bid for SFR in France in terms of structure."
With many U.S.-based banks already conflicted given thatthey have signed onto the Sprint-Softbank bid, theirinternational rivals HSBC and BNP embraced the chance to financethe Iliad approach.
Five global banks - JPMorgan Chase & Co, Goldman SachsGroup, Deutsche Bank AG, Bank of America Merrill Lynch andCitigroup Inc - have agreed to finance Sprint's proposal to buyT-Mobile, sources told Reuters in June.
BIG TARGET
In bidding for T-Mobile US, Iliad is taking aim at a targetmuch bigger than itself. Iliad's market capitalisation was justabove $16 billion before Friday's share drop, compared withabout $25 billion for T-Mobile US.
Iliad has 8.6 million mobile customers and 5.7 million inbroadband, and generated 2013 sales of 3.75 billion euros, or $5billion. T-Mobile US has 50 million mobile customers and 2013revenue of $24.4 billion
David Moss, head of European equities at F&C, who does notown Iliad shares, cast doubt on Iliad's ability to win the deal.
"There are no synergies. They've come up with 10 billion butwe don't know where that's come from," he said. "Shocked,surprised, bemused are the words that come to mind."
Metzler Asset Management's Heise was cautiously optimistic.
"Iliad has shown in France that it can roil a market withits low cost base. But that may not work so fast and easily inthe U.S., where the market conventions are different: higheraverage revenue per customer, different product packages, morepromotion expenses," he said.
THREAT TO CONSOLIDATION
Shares in rival French telecom companies fell on Friday asinvestors eyed the implications of Iliad - potentially acatalyst for consolidation among the four mobile players there -looking elsewhere for growth, leaving the industry at home tosuffer continued erosion of margins and cut-throat competition.
France has been in the throes of a price war since 2012sparked by Iliad's Free Mobile brand, which has sent prices downby one-third.
Third-place mobile carrier Bouygues has become the maintarget after losing out in a bidding war in April to buy biggerrival SFR to cable group Numericable. Itsshares were down 4 percent. Former monopoly Orange's shares were down 2 percent, while Iliad's stock had pared its losses by1255 GMT to trade down 5 percent.
Iliad made an informal offer to buy Bouygues earlier thisyear, and also took part in talks with Orange about a joint bidfor Bouygues, sources told Reuters. Bouygues rejected theseovertures on grounds the prices being floated were too low.
(1 US dollar = 0.7468 euro) (Additional reporting by James Regan in Paris, Simon Jessop inLondon, and Gwenaelle Barzic in Paris; Editing by Andrew Callusand Mark Potter)