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World No. 1 tennis ace Novak Djokovic has chosen an unusual way to spend his millions in winnings from tournaments and sponsorships - he is buying up the world's supply of an expensive cheese made from donkeys.

The Serbian star, who is the current Australian Open winner and will finish the year at the top of the ATP rankings, has bought up all of the cheese produced in his home country, which is known as pule, according to Britain's Daily Telegraph. The tennis star has snatched up the pricey cheese, which can cost over $500 per pound, for a chain of restaurants he is opening.

Pule, a smoked donkey's milk cheese that comes in a white, crumbly form, comes with such a high price tag because one kilogram of the delicious delicacy requires 25 liters of donkey milk.

The cheese is produced in the Serbian town of Zasavica at a farm that bears the same name as the town. Slobodan Simic, the manager, told the Telegraph that the milk used in the cheese was raised on one of Serbia's most famous wildlife and nature reserves.

He added that he is pleased to be in business with Djokovic, one of Serbia's biggest global stars. He has sold him his farm's entire year's supply.

"It will save a lot of effort having to deal with various restaurants, with only one customer buying the lot we don't have to worry too much about salesmen, he said, "It is a great vote of confidence as well in what we do here."