Simmering conflict with Russia has not stopped a number of U.S. and European energy giants from recently investing or exploring investments in Ukraine's fledgling energy sector, according to a former Ukraine government minister who plays a key role in negotiating energy deals in the region.
Yuriy Boyko, an ethnic Ukrainian and former energy minister under ousted President Viktor Yanukovich, told CNBC that he has met with senior executives of Chevron, ExxonMobil, Royal Dutch Shell and Halliburton about investments or potential investments in the country.
Boyko, who is running for president in Ukraine, is trying to encourage more American and European investment in Ukraine's nascent energy sector.
"It's very important for our country," he said. "We must provide more and more gas on our territory...to purchase less from other countries, especially Russia."
Ukraine is known for pipelines that transport Russian oil and gas through its territory into Europe, but sources who spoke with CNBC pointed out that the country has its own shale gas reserves and a favorable pricing environment for producers.
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Cameron Van Ast, Chevron onshore Europe spokesman, confirmed that the San Ramon, California, company is developing a presence in Ukraine.
"The Production Sharing Agreement (PSA) signed in November in Kiev is a precursor to an initial 5-year exploration program to confirm the presence of a hydrocarbon bearing formation and understand its reservoir characteristics," he told CNBC.
Boyko was one of the main forces behind negotiating that agreement in November, and he currently plays a mediating role on energy matters between the governments of Ukraine and Russia. He put Chevron's expected exploration investment at $350 million, within two areas of western Ukraine.
Van Ast said that Chevron's efforts are ongoing despite serious unrest in Ukraine, especially in the eastern part of the country. "We are monitoring the situation, but we continue to have a team in Ukraine who are engaging with key stakeholders on a daily basis," Van Ast said.
Royal Dutch Shell is currently the biggest player in the Ukrainian market. The company declined to comment on specific dollar figures, but said that it has ongoing operations in the region.
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Shell spokesman Curtis Smith told CNBC that it employs about 2,500 people in Ukraine, many as contract workers. The company is involved in two exploration projects, both in eastern Ukraine, including in the Donetsk and Kharkov regions, the most troubled in the country.
To date, the company said operations have not been affected despite rising tension in those areas.
"We continue to prepare for exploration activities on Yuzivska area," Smith told CNBC. "We monitor trade controls and sanctions closely and will respond appropriately to ensure that we comply with all applicable international sanctions and related measures."
Exxon 'interested' in license
Boyko said Shell is expected to spend $400 million for exploration of Yuzivska, a Ukrainian natural gas field that was discovered in 2010 and is set to begin production in 2017. It's in eastern Ukraine near the Russian border.
Patrick McGinn, an ExxonMobil spokesman, told CNBC that Exxon does not have operations in Ukraine, though it has explored the idea.
"We were negotiating for almost two years with Ukraine for a license in the Black Sea, but we were unable to come to a final agreement," McGinn said. "We remain interested in that license, but are on hold due to current circumstances."
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McGinn said that they are not holding any official discussions at the moment because the Black Sea license was their main focus.
Boyko, who was part of the Black Sea talks as well, said he hopes to retain Exxon's interest in this project.
Halliburton did not respond to CNBC requests for comment.