Ukraine Tensions Loom Over Iran Nuclear Talks

No Disruptions So Far, But Russia Warns It Might Raise Stakes in Clash With the West.

Tensions over Ukraine didn’t’ disrupt the latest round of Iran nuclear talks, but Russia’s top negotiator warned his government might use its cooperation as a lever to “raise the stakes” in response to pressure from the U.S. and European Union.

The warning by Deputy Foreign Minister Sergei Ryabkov on Wednesday followed U.S. and EU announcements of sanctions against Russia over its attempts to annex Crimea. It was the most serious threat of retaliation for Western pressure.

“We wouldn’t like to use these talks as an element of raising the stakes, given the mood in certain European capitals, Brussels and Washington,” Mr. Ryabkov told Russia’s Interfax news agency. “But if we are forced to do this, we will go down the path of taking measures in response.”

Western and Iranian officials at the talks in Vienna said that concerns the crisis in Ukraine would complicate the negotiations and divide the six-power group proved unfounded at this week’s talks. The six powers include the U.S., Russia, Britain, France, China and Germany.

The talks between the six powers on one side and Iran on the other are aimed at sealing a comprehensive deal by July that would prevent Tehran from developing nuclear weapons. The second round wrapped up Wednesday after two days of negotiations that tried to bridge gaps over Iranian plans for a heavy-water reactor.

But much of the attention headed into the talks focused on the risk that the escalating crisis over Crimea would weigh on the forum.

Iranian officials have talked of an oil-for-goods deal in which Russia could sign contracts to build new nuclear reactors in Iran. That could weaken international energy sanctions and give Tehran more access to nuclear material. However a deal hasn’t been confirmed.

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