Vice President Joe Biden says the United States is ready to hold direct talks with Iran over its nuclear program — provided that the country's top leader is serious about such discussions.

Biden, attending a security conference in Munich, Germany, spelled out conditions for the talks, reports Reuters: "We have made it clear at the outset that we would be prepared to meet bilaterally with the Iranian leadership, we would not make it a secret that we were doing that, we would let our partners know if that occasion presented itself. That offer stands, but it must be real and tangible and there has to be an agenda that they are prepared to speak to. We are not just prepared to do it for the exercise."

Iranian diplomats have been talking for months with an international group of countries from the U.N. Security Council plus Germany, but The Washington Post says the talks haven't progressed. Biden says that can change: "The ball is in the government of Iran's court."

Biden is on a brief three-nation tour; after stopping in Germany on Saturday, he moves to France for talks with French president Francois Hollande who's visiting Mali on Saturday. Then he'll travel to Britain to see Prime Minister David Cameron, says the BBC.

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