KYIV, July 1 - Executive Director of national joint-stock company Naftogaz Ukrainy Yuriy Vitrenko has denied comments from Russia's Gazprom Head Alexei Miller about the absence of proposals about gas swap from Naftogaz and proposed to take this proposal seriously.

"Gas swap, as a backup option if Gazprom does not want to conclude a contract for the reservation of capacity for transit, was offered to Gazprom in the spring of 2018 in my official talks with the head of the Gazprom delegation, Mr. (Alexander) Medvedev, at that time, Deputy Mr. Miller," Vitrenko wrote on his Facebook page.