According to a U.S. embassy in Belgrade cable from 2007 sent to Washington, tycoon Miroslav Miskovic, the owner of Delta Holding saying his fortune "was made on the backs of the Serbian people as they struggled through crippling sanctions and hyperinflation while he collected on their misery" and “his company built up through corruption”.

The cable, obtained by WikiLeaks and seen by Reuters, cited evidence the U.S. embassy had obtained that Delta Holding had prospered because he was a part of outrageous political corruption.

WikiLeaks writes that “he dominates banking, insurance, and consumer goods in Serbia, after obtaining massive wealth as a beneficiary of official corruption by Slobodan Milosevic in the mid-1990s”.

Miskovic was a member of Milosevic's government six months in 1990. According to the cable, Yugoslavia's director of customs at the time Mihalj Kertes, who was very close to Milosevic, granted special treatment to Delta company, including a 45-day grace period to pay customs duties. Other firms had to pay on the spot.

The deal also allowed Delta to unload cargo in Belgrade rather than at the border, and allowed him to keep the goods in storage at customs until he needed them, the cable said.

According to one customs official cited in the cable, the firm sometimes paid no duties at all.

WikiLeaks wrote also that the embassy had obtained a copy of a 1996 letter from customs director Kertes allowing Delta special treatment, and the text of the letter was appended to the cable.

Customs officials contacted by Reuters on Friday did not respond by Monday.

Miskovic declined comment on the cable, saying he never gives media interviews, and Jelena Krstovic, head of Delta's corporate communications department, also declined to comment in detail about the allegations, saying only that "Delta Holdings has always worked according to Serbian law."

Delhaize, international is a food retailer headquartered in Belgium, which this month agreed to buy Serbia's largest retail chain, said in a statement to Reuters it had and would continue to act "in full transparency and according to all legal obligations in the process to acquire 100 percent of Delta Maxi Group", adding that the deal clearly has the full support of Serbia's government.

Officials at Delhaize declined to respond to questions about whether the Belgian company knew of the allegations when it negotiated to purchase Delta Maxi, or whether the allegations would affect, or had affected, the process of the bid.