UPDATE 3-Six companies eyeing Alcoa's Italy plant

By Francesca Piscioneri and Alberto Sisto

MILAN, Sept 20 (Reuters) - Three more potential buyers have emerged for an Italian plant being closed by U.S. aluminium maker Alcoa, bringing the total number to six and raising hopes of a rescue deal that could save more than 500 jobs.

Alcoa has decided to shut its smelter in Sardinia, an island blighted by high unemployment and slow economic growth, blaming high power prices for undermining its competitiveness.

But it has pledged to maintain the plant for a year in case a buyer comes forward, and Prime Minister Mario Monti's government is under intense pressure from unions to secure a deal at a time of austerity and deep economic recession.

"There are two other groups that expressed an interest to the government late last night," a government source said on Thursday, without providing any names.

Separately, the president of the Sardinia region said a large Chinese group was also among those interested.

Ugo Cappellacci told Italian radio that a Chinese group had asked for access to the data room, adding: "It is a first-contact stage and confidential, and so they have not yet given the identity of the group - except to say it is big."

Swiss companies Glencore and Klesch as well as Italian wind power company Kite Gen Research previously expressed interest.

An unsourced report in Italian daily MF said the Chinese company involved was Hong Kong Wan Hao International Trading. That company was not immediately available for comment on Thursday.

Alcoa sounded cautious on Thursday, saying "it has not received any expressions of interest that are viable or different to those previously considered during the thorough sale process."

In a statement, the company added it was continuing the curtailment process and remained open to discussing a sale of its Sardinian plant.

On Wednesday a Sardinian official said commodities trader Glencore was expected to present a letter of intent to buy the plant in 10-15 days.

Glencore's interest is conditional on the government being able to guarantee steeply discounted power prices at the plant.

Asked if Europe might block such a discounted price scheme, Cappellacci said he had spoken to EU Commission vice-president Antonio Tajani.

"We have reason to believe a yes will arrive," he said.