Russia`s gas chief and deputy prime minister scoffed on Sunday at what he saw as hysterical behaviour from other countries about paying for gas, just days after Moscow threatened to turn off supplies to Ukraine. "Negotiations regularly set off disputes that we can`t understand. Sometimes even hysterics break out," Russia`s first deputy prime minister Dmitry Medvedev said in remarks reported by Interfax news agency. He is also chairman of gas export monopoly Gazprom (GAZP.MM: Quote, Profile, Research), the world`s largest gas producer, which supplies the European Union with a quarter of its gas needs. Gazprom said last week it might reduce gas supplies to Ukraine if the country failed to repay a $1.3 billion debt for earlier deliveries. The threat has caused unease in the EU as a previous pricing dispute between Russia and Ukraine, the most important transit route for Russian gas to Europe, resulted in significant supply reductions to some EU countries early in 2006. Medvedev denied there was any political link to the row, which erupted just after Ukraine voted in elections last Sunday, which some analysts said was a Russian bid to pressurise Kiev parties to form a government that would take a pro-Moscow line. "It`s about time our partners got used to the idea that one has to pay for one`s gas, pay on time and in accordance with the contracts that have been signed," said Medvedev. "This problem will be solved when Russia gets the money." "The gas price for Ukraine will be based on market factors, as is done for all our partners," he said. "If our partners don`t pay us, we are simply forced to look for other mechanisms of financing. And that is bad for the financial budget of such a large company," Medvedev said. Gazprom said on Friday it would pursue talks with Ukraine next week on supplies and Kiev`s debts, despite earlier announcing that the issues had been resolved. A new round of talks would start on Monday, when Ukraine`s Energy Minister Yuri Boiko returns to Moscow, stated Gazprom. Ukraine`s state-owned gas company Naftogaz reassured markets again on Friday that it could meet all transit commitments.