PRAGUE -- Slovakia's Foreign and European Affairs Minister Juraj Blanar urged the European Union (EU) to address Ukraine's decision to halt Russian oil transit to Slovakia and Hungary, saying the decision violates the EU-Ukraine association agreement.

"We consider the measures introduced by Ukraine in connection with the stoppage of the transit of oil from Russia's Lukoil to Slovakia and Hungary to be a clear violation of the provisions of the Association Agreement concluded between the EU and Ukraine," Blanar said in a statement on Monday.

Together with his Hungarian counterpart Peter Szijjarto, they have submitted an urgent call to the European Commission for action on the matter, he added.

"The European Commission is supposed to act as a guardian of the treaties and of compliance with EU law, which Ukraine as an associated state is also obliged to follow. We therefore consider it to be essential that the Commission should act immediately in this case," he noted.

According to Blanar, the EU sanctions against Russia, which Slovakia has opposed several times, have once again proven to have a greater negative impact on Slovakia and the EU than on Russia. "The Slovak Republic has an exemption for oil imports until the end of the year," Blanar said, adding that "the Ukrainian side has made it impossible to apply this exemption."

Slovakia's economy ministry said last week that oil deliveries from Russian company Lukoil have stopped flowing to Slovakia via Ukraine following the company's inclusion on a Ukrainian sanctions list. The move also affected Bratislava-based refiner Slovnaft.

On Tuesday, European Commission trade and agriculture spokesman Olof Gill said that the Commission has received a letter from Hungary and Slovakia regarding Ukraine's decision to block the passage of Russian oil and is "studying the contents of this letter."