In 2016, former vice president of the United States, Joseph Biden, requested previous president of Ukraine, Petro Poroshenko, not to let former prime minister of Ukraine, Volodymyr Groysman, dismiss board chairperson of the Naftogaz of Ukraine national joint-stock company, Andrii Kobolev. This follows from the records of the talks between Biden and Poroshenko dated December 19, 2016 published by non-affiliated member of the Ukrainian Parliament, Andrii Derkach, Ukrainian News Agency reports. He added he knew that Groysman advocated Kobolev’s dismissal. Poroshenko promised Biden to monitor the situation. Derkach also said that Americans wanted to preserve Kobolev to jointly earn on the reverse of Russian natural gas with a mark-up of EUR 50 per thousand cubic meters. As Ukrainian News Agency earlier reported, in 2016, former vice president of the United States, Joseph Biden, requested then president, Petro Poroshenko, to guarantee non-prosecution of former prime minister, Arseniy Yatsenyuk, in case of his dismissal. In response to such a request, Poroshenko provided the respective personal guarantees. On May 19, Derkach published the records of the Biden and Poroshenko talks, which indicated that the former president of Ukraine agreed a number of key decisions with the U.S. Secretary of State and fulfilled his requests. On June 22, Derkach published the second part of the records.