Russia may revise its stance in the Iranian nuclear talks amid tensions with the West over Ukraine, a senior diplomat warned Wednesday. Russia’s Deputy Foreign Minister Sergei Ryabkov said, according to the Interfax news agency, that Russia didn’t want to use the Iranian nuclear talks to “raise the stakes,” but may have to do so in response to the actions by the United States and the European Union.

The statement is the most serious threat of retaliation by Moscow after the U.S. and the EU announced sanctions against Russia over its annexation of Ukraine’s Crimea region. MORE