Ukraine overpays up to $6 billion annually due to the terms its current gas contract with Russia, which means $60 billion for ten years, Ukrainian President Viktor Yanukovych told the Kommersant daily. Kiev is seeking to review the gas contract with Moscow signed by then prime minister Yulia Tymoshenko and Russian premier Vladimir Putin in 2009, saying the gas price it pays is unfair. Tymoshenko is now charged with abuse of office over the contract signing. \"The overpayment for us totals $5-6 billion, or some 20% of the country\'s annual budget,\" Yanukovych said in the interview. Ukrainian Foreign Minister Kostyantyn Hryshchenko said on Monday that Kiev would not join the Moscow-led Customs Union of Russia, Belarus and Kazakhstan, a condition for discounts on Russian gas prices. Ukraine has also ruled out a merger between Russian energy giant Gazprom and Ukraine\'s Naftogaz, which could also reduce prices for Kiev. Yanukovych reiterated in the interview that Kiev would seek international arbitration if Russia did not offer a better deal on gas supplies.