* Sacyr must refinance 4.9 bln euros debt by Dec. 21
* Creditor banks want sale of half its 20 percent of Repsol
* Repsol itself potential buyer of 2.7 bln euro stake
By Carlos Ruano and Tracy Rucinski
MADRID, Dec 19 (Reuters) - Spanish oil major Repsol may buy up to 10 percent of its shares from Sacyr , as foreign industrial buyers faded before a looming deadline for the debt-laden builder to refinance, sources said.
A syndicate of banks led by Bankia, Citigroup and Santander, wants Sacyr to come up with about half the 4.9 billion euros ($6.4 billion) it owes to be able to refinance the remainder before a Dec. 21 deadline, sources with knowledge of the refinancing talks told Reuters on Monday.
Indian conglomerate Essar, Russian group Lukoil, Chinese oil major Sinopec, and an unnamed Latin American oil group had been tipped as possible buyers of the Repsol stake, worth about 2.7 billion euros.
The sources said that, while all options remain open, the likelihood of sealing a deal with a foreign industrial buyer at an attractive price before Wednesday looked slim.
Sinopec and other Chinese state-owned oil companies do not have a track record of taking minority stakes in established listed oil and gas companies. When a Chinese buyer was reported to be eyeing Sacyr's Repsol stake in 2008, industry minister Miguel Sebastian said he would like a Spanish buyer.
Repsol's other main shareholders, Caixabank and Mexican group Pemex, are not likely buyers, leaving Sacyr with the option of placing 8-10 percent on the market or Repsol itself buying a chunk to hold as treasury stock.
"It is not such a bad deal for Repsol. The stock is cheap, they would be buying at a good price and can sell the shares later," Alvaro Navarro, equity analyst at Intermoney Valores in Madrid said. "And the risk of Sacyr selling at a discount disappears."
Analysts said hedge funds and pension funds would be eager to buy small stakes at a good price in an oil company with recurring revenues, exploration projects and an attractive dividend policy.
Repsol declined to comment, while Sacyr was not available to comment. A Sinopec media official said the company had no information available on a deal to buy part of Repsol from Sacyr, when reached by Reuters.
Repsol shares were up 2.1 percent at 22.535 euros by 1320 GMT, outpacing a 1.5 percent gain on Spain's blue chip index , while Sacyr shares were down 0.1 percent.
Sacyr ran into debt trouble when it acquired 20 percent of oil group Repsol for 6.5 billion euros just before the global financial crisis and the collapse of Spain's property and construction bubble.
It was a time when other Spanish builders, such as ACS , Acciona and Ferrovial, were also looking to diversify away from their core construction business after a decade-long boom.
Sacyr's ill-fated investment led to a battle among management and shareholders which ended in the ousting of long-time chairman Luis del Rivero and now threatens the company's very survival.
The Repsol stake is worth about 5.4 billion euros, meaning del Rivero's successor, Manuel Manrique, has little choice among unattractive options to pay back the loan.
Sacyr has net debt of 11.4 billion euros and scarce free cash flow given Spain's prolonged construction downturn. It has already put other assets like rental business Vallehermoso up as collateral.
Aside from the Repsol loan, Sacyr faces expiries on 575 million euros of debt in 2012 and 952 million in 2013.
"The talks (on the Repsol stake) are vertiginous. Anything is still possible," a source with knowledge of the negotiations said.