UPDATE 1-Management of Slovene food retailer Mercator resigns

(Adds details, background, share price)

* Disagreements with owners

* Resignation a day before shareholders meeting

By Marja Novak

LJUBLJANA, March 29 (Reuters) - The five-member management board of Slovenia's largest food retailer Mercator resigned late on Thursday over disagreements with the owners of the company, Mercator told Reuters.

"The reason for the resignation is lack of confidence of the bigger owners (in the management)," Mercator's spokeswoman Mojca Briscik said, giving no further details.

Mercator's chief executive Ziga Debeljak told Slovenian news agency STA that the board was willing to stay on until Sept. 30 if that would be the wish of the owners.

The conflicts between the management and the owners, which include local banks and investment companies, started last year when the management refused to allow due diligence of the company that would enable the sale of a majority of Mercator to Croatian rival Agrokor.

The resignation came a day before a meeting of Mercator's shareholders who are expected to nominate new members of the supervisory board that would have the power to change the management board.

Last year 12 local lenders and investment firms tried to sell their joint 52.1 percent stake in Mercator but the sale was suspended after Mercator refused to allow due diligence to Agrokor which was the best bidder.

According to local media Agrokor offered 221 euros per Mercator share, valuing the whole company at 832 million euros ($1.1 billion).

Mercator said in November it would not allow Agrokor to perform due diligence because the company was its biggest competitor in the region and there was a risk the sale could be stopped by competition authorities in Bosnia, Croatia, Montenegro and Serbia, where both are present.

Mercator also operates stores in Albania and Bulgaria. Its share closed unchanged at 125 euros on Thursday, before the news of the resignation was released, while the blue chip SBI index eased 0.47 percent. ($1 = 0.7532 euros) (Reporting By Marja Novak; Editing by Phil Berlowitz)