* Strategic Holdings raises Club Med stake above 10 pct
* Source says Strategic Holdings opposed Gaillon Invest bid
* Gaillon's offer for Club Med closes May 23
* Strategic Holdings' controller Bonomi may seek board seat
* Strategic Holdings says does not want control of group (Adds Strategic Holdings regulatory filing)
By Dominique Vidalon
PARIS, May 20 (Reuters) - A fund led by Italian businessman Andrea Bonomi has become Club Mediterranee's largest shareholder and will seek to join its board, further clouding the prospects for a long-running takeover bid for the French holiday firm.
The stakebuilding by Bonomi's Strategic Holdings comes after another shareholder, Italy's Benetton family, last week removed its support for the 557 million euro ($764 million) offer, launched a year ago by China's Fosun International and French private equity firm Ardian via an investment vehicle called Gaillon Invest.
A source close to the matter told Reuters the latest share purchase by Bonomi's Strategic Holdings was "a way to torpedo the takeover offer."
Gaillon's 17.50 per share offer is due to close on May 23, and needs 50 percent support.
Gaillon so far has more than 30 percent acceptances, but the offer has hit legal challenges from shareholders who want more money and is less than the current stock market value of Club Med.
The fund said in a regulatory filing on Tuesday that it would continue to raise its stake after increasing it to 10.07 percent on Monday. It said it was not seeking to take control of the company or force a change in its strategy, but had the funding to buy a further 10 percent.
Club Med declined to comment. Gaillon Invest said it was waiting for Strategic Holdings to clarify its intentions.
Fosun, with a 9.96 percent stake, and Ardian, with 9.4 percent, have said they want to accelerate Club Med's shift to fast-growing emerging markets such as China to counter weak growth in Europe.
Strategic Holdings bought an additional 427,635 Club Med shares at 18.96 euros each on May 19, raising its total stake to 3.36 million shares, the filing said. Strategic Holdings said it now holds 9.05 percent of Club Med's voting rights.
"Strategic Holdings wants to work with Club Med's management and may continue to buy more shares as it believes this company has a future," a source close to BI-Invest, the parent company of Strategic Holdings, told Reuters on Tuesday.
Club Med shares closed up 0.7 percent at 19.10 euros each, their highest level since 2008.
A French court on April 29 rejected a shareholder challenge to Gaillon's offer that had delayed it for almost a year. The shareholders, led by the Association for the Defence of Minority Shareholders (ADAM) and Charity Investment Asset Management (CIAM), had challenged it on the basis that it was too low.
Gaillon has also taken legal action against the Benetton family after it removed its backing for the bid and added the weight of its 2 percent stake to those demanding a higher price, a source familiar with the matter said on Sunday.
Founded in 1950 and listed since 1966, Club Med was a pioneer of the all-inclusive holiday resort.
The Gaillon bid came at the end of a tough decade for the business, one of stiff competition and in which it made an unsuccessful expansion into services. Its more recent drive to recast itself as an upmarket operator has also been hampered by a weak European economy.
$1 = 0.7289 Euros Reporting by Dominique Vidalon, Matthieu Protard and Andrew Callus; Editing by Erica Billingham