2009 Russia–Ukraine gas dispute

In 2009, Russian natural gas company Gazprom refused to conclude a supply contract unless Ukrainian gas company Naftogaz paid its accumulating debts for previous gas supplies. The dispute began in the closing weeks of 2008 with a series of failed negotiations, and on January 1, 2009 Russia cut off gas supplies to Ukraine. On January 7 the dispute turned to crisis when all Russian gas flows through Ukraine were halted for 13 days, completely cutting off supplies to Southeastern Europe, most of which depends on Russian gas, and partially to other European countries.

Throughout the crisis the Russian and Ukrainian sides blamed each other for the cutoff. On January 11 and 12, the European Union deployed an independent monitoring mission in an attempt to solve the crisis, but the mission met with little success. On January 12, Gazprom announced that it was willing to start delivering gas through the Sudzha metering station into the pipeline that traverses Ukraine towards Southeastern Europe, but Ukraine refused the offer for technical reasons and instead suggested an alternative route through Valuyki and Pisarevka metering stations, additionally insisting that supplies be fully restored. This was refused by Gazprom.

On January 18 the dispute was resolved when Russian Prime Minister Vladimir Putin and his Ukrainian counterpart Yulia Tymoshenko negotiated a new contract that covered the next ten years. (On October 11, 2011, a Ukrainian court sentenced Tymoshenko to seven years in prison for abuse of office in her role of signing this deal. In the aftermath of Euromaidan, this sentence was overturned under suspicion of being political reprisal from her 2010 Presidential election rival Viktor Yanukovych, and the judge who handed down the sentence fled the country after being charged with giving a "deliberately unlawful verdict.")

Gas flows to Europe restarted on the morning of January 20, and were fully restored within two days. In the aftermath, Gazprom was estimated to have lost US$1.5 billion in revenues due to lack of sales, and Ukraine was speculated to have incurred major economic losses. Analysts point out that the crisis had a negative and possibly irreversible impact on the reputations of both Russia as an energy supplier, and Ukraine as a transit country. There is no consensus amongst analysts on who bore the most responsibility for the crisis. Due to the absence of international monitors on both sides of the Ukrainian pipeline system, it is impossible to determine with certainty who was responsible for interrupting gas flow to Europe.