Ukraine is running low on coal because of violence wracking in the country, according to a Ukrainian coal producer and a private equity firm that makes energy investments in Ukraine.
Pelicourt, the private equity firm, and Donbass Energy, which has operations ranging from coal mining to electricity generation, told CNBC that Ukraine could run out of coal supplies because of the destruction of the rail lines by Russian separatists.
According to Robert Bensh, managing partner of Pelicourt, the major mining region of Ukraine—also known as Donbass—could cease getting its coal to electricity producers within the next 40 days. The claims by Pelicourt and Donbass were presented last week to Ukrainian Energy Minister Yuriy Prodan.
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CNBC's attempts to reach Prodan for comment were unsuccessful.
The Kiev Post published an infographic last week illustrating infrastructure problems in eastern Ukraine, including damage to factories, roads and power stations.
Johns Hopkins University fellow Donald Jensen told CNBC that Russia can exploit energy shortages this winter—especially natural gas—but he played down the immediate threat to Ukrainian coal supplies.
For the time being, Jensen said, "the Ukrainians can probably get by."
Pelicourt owns oil and gas assets in Ukraine and is the largest shareholder of Cub Energy, a firm that owns prospective natural gas fields in Ukraine and trades on the Toronto Stock Exchange. On its website, Cub Energy says it "aims to rapidly develop this asset portfolio (gas basins) to take advantage of natural gas prices." Ukraine has among the highest natural gas prices in Europe.
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Russian President Vladimir Putin is set to meet with his Ukrainian counterpart, Petro Poroshenko, in Minsk, Belarus, on Aug. 26, according to the Kremlin.
It would be the first meeting between the two since Poroshenko took office in early June.
—By CNBC's Dina Gusovsky