* Vietnam selling up to 54 percent in Sabeco
* Some bidders discouraged by rich valuations - sources
* Trade ministry says Thai Bev unit keen to bid for 51 pct
* Ministry set to conduct auction on Monday
By Mai Nguyen and Anshuman Daga
Ho CHI MINH CITY/SINGAPORE, Dec 17 (Reuters) - Vietnam is set to auction an up to $5 billion stake in top brewer Sabeco on Monday, with Thai Beverage the only potential bidder to have expressed interest in a majority stake.
The keenly anticipated sale of the state-owned maker of Bia Saigon gained momentum in recent months after being hampered for years by political resistance, fickle policy-making and complications over valuations.
The government has set a minimum sale price of 320,000 dong or $14.10 a share for Saigon Beer Alcohol Beverage Corp (Sabeco), whose shares have nearly trebled to 309,200 dong since its listing a year ago.
Thai Beverage, through a partly-owned Vietnam unit, is the only company which has expressed interest in owning more than 25 percent of the company, which has roughly 40 percent of the beer-loving Vietnamese market.
So far no formal bid had been made.
Vietnam's young population and booming economy should make Sabeco an attractive asset for global brewers hoping to expand in Southeast Asia, but a high minimum bid price and foreign ownership limits appear to have turned off potential buyers.
Sabeco's foreign ownership is capped at 49 percent. With 10 percent already in foreign hands, that leaves only 39 percent on the table for overseas buyers at Monday's auction. Local bidders can bid for a majority stake of up to 54 percent. Heinken holds a 5 percent stake.
"There's a disconnect between what the government wants to achieve and how international brewers view this auction," said one person familiar with the matter.
"In a normal auction, bidders are fully aware of what stake they'll end up owning and bid for it accordingly," said the person, who was not authorised to speak to the media.
Unlike similar sales in developed markets, where investors are whittled down over several rounds and offers can be adjusted, Sabeco bidders need to submit a single offer for a specific number of shares in a sealed envelope in one round.
Thai Bev, controlled by tycoon Charoen Sirivadhanabhakdi, was keen to acquire Sabeco as part of a strategy to expand outside its home market, sources told Reuters. The company had already lined up bank guarantees to support the bid by its Vietnam unit, sources said.
There was no immediate response from Thai Bev to a query from Reuters.
Reuters previously reported that the auction was drawing the interest of brewing groups such as Anheuser-Busch InBev , Kirin Holdings, Asahi Group Holdings and San Miguel, but there is no clear sign of whether they have participated in the auction so far.
The government's minimum price for the 54 percent stake on offer valued Sabeco at about 36 times core earnings, more than double the trading multiples of around 15 for some global peers, according to Reuters data.
Vietnam's trade ministry is expected to announce the bidding result on Monday afternoon. (Reporting by Mai Nguyen and Anshuman Daga; Additional reporting by Chayut Setboonsarng in BANGKOK; Editing by Stephen Coates)