BELGRADE (Reuters) - Serbia is shoring up its crude oil and fuel reserves as the country presses on with talks with the United States and Russia to avoid U.S. sanctions on its oil company NIS, energy minister Dubravka Djedovic Handanovic said on Wednesday.

Gazprom Neft and Gazprom hold stakes of 50% and 6.15% respectively in NIS, which operates the sole oil refinery in Serbia.

"We are continuing talks with both the United States and Russia to reach a solution," Djedovic Handanovic said in a live TV broadcast.

Following U.S. sanctions against Russia's oil sector on January 10, Gazprom Neft was given 45 days to exit ownership of NIS, which operates Serbia's sole oil refinery in Pancevo, just outside the capital Belgrade. 

Serbia, an historical ally with Russia, has submitted a formal request to the U.S. Treasury Department for a waiver of sanctions for 90 days to allow it to consider a "sustainable solution that would lead to the lifting of sanctions."