A senior Russian diplomat says Moscow may change its stance in the Iranian nuclear talks amid tensions with the West. Deputy Foreign Minister Sergei Ryabkov was quoted Wednesday as saying by the Interfax news agency that Russia didn’t want to use the Iranian nuclear talks to “raise 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 the Ukrainian crisis.