Ukrainian President Viktor Yanukovych announced significant progress in talks with Russia on revision of the Russian-Ukrainian gas agreement, Ukrainian UNIAN news agency reported on Sunday. "Significant progress was made during the negotiations, what gives a hope to achieve concrete results soon in the best interests of both countries," Ukrainian administration said citing Yanukovych. Kremlin also announced substantial progress with the gas agreements. "Sertain agreements were made during yesterday's talks between Russian President Dmitry Medvedev and Ukrainian President Viktor Yanukovych," Russian president's spokeswoman, Natalya Timakova said. Medvedev and his Ukrainian counterpart Yanukovych held an informal meeting on Saturday to discuss ways to settle the long-running deadlock. Ukraine is seeking to review gas deals with Russia, saying its 2009 contract's gas price formula is unfair. Former Prime Minister Yulia Tymoshenko is now on trial for signing the deal. Moscow has tied the price for gas to the international spot price for oil, which have risen strongly since that year due to the instability in the Middle East.