Due to Budapest's unwillingness to abandon Russian oil, Adviser to the Ukrainian Minister of Energy Lana Zerkal warned, on Thursday, May 26, that Kiev may decide to do something about the Hungarian Druzhba oil pipeline that passes through Ukrainian territory. Zerkal, at the Kiev Security Forum, said that "there is a wonderful lever in the hands of Ukraine, which is the Druzhba oil pipeline."

According to the Ukrainian official, Hungary is "taking advantage" of the crisis in Ukraine to negotiate a prerogative for energy with the EU. It would be "appropriate if something happened" to the oil pipeline, but the Ukrainian government will have the last say on whether it wants to communicate with Hungarian Prime Minister Viktor Orban in "the language that he understands and which he imposes on the EU."

Read more: EU failed convincing Hungary to sanction Russian oil

Hungarian Foreign and Trade Minister Peter Szijjarto said on May 16 that Budapest expects the European Commission to propose an 18 billion euro ($18.8 billion) investment plan to help mitigate the effects of a possible Russian pipeline oil embargo, which is expected to result in a more than double increase in energy prices in the country.

The Druzhba oil pipeline extends from Russia's Samara region to Bryansk, and then through Belarus, Ukraine, Poland, Germany, the Czech Republic, Slovakia, Hungary, Latvia, and Lithuania. The pipeline transports crude oil.

Previously, Hungary's Prime Minister Viktor Orban said that the EU proposal for an embargo on Russian energy resources is "tantamount to an atomic bomb" for the Hungarian economy, which will need at least five years to diversify its energy supply - under the EU's proposal, they only have till 2023. Hungary and Slovakia are both dependent on Russian oil.