(Updates with company confirmation, quote, share price)
LJUBLJANA Jan 29 (Reuters) - Slovenia's largest food retailer Mercator on Tuesday reported a net loss of 103.6 million euros ($139.63 million) in 2012, versus a profit of 23.5 million euros in the previous year.
The company blamed the loss on a fall in the value of some of its assets, including real estate, plus tougher competition and a worsening economic situation.
"The competition in the region is getting tougher which is reducing our profit margins," Mercator's chief executive Toni Balazic told reporters at a news conference.
He said profits were also hit by the depreciation of the Serbian dinar and by an increase of the value-added-tax in Croatia.
The retailer operates stores in Slovenia, Serbia, Croatia, Bosnia and Montenegro, while it is this year planning to sell its units in Albania and Bulgaria.
Sales fell to 2.87 billion euros from 2.93 billion the year before.
Mercator also said it reduced net debt by 7.6 percent in 2012 to about 1 billion euros. The company said it planned to cut costs and improve productivity in 2013 to return to profit.
In December, Mercator's owners resumed an attempt to sell their joint 53.18 percent stake in the company after an earlier attempt was not successful.
Shares of Mercator, which has market capitalisation of 527 million euros, closed 0.04 percent lower at 140 euros on Tuesday before the results were released, while the blue-chip SBI index gained 0.86 percent.
Mercator's results were initially reported by daily Finance on its website.
($1 = 0.7420 euros) (Reporting By Marja Novak. Editing by Jane Baird and Jane Merriman)