Welcome to the News Hour. Today, across two continents, the U.S. confronted two very different nuclear challenges.

For the first time since last year's war in Iran, U.S. and Iranian diplomats restarted diplomacy, focused on that country's nuclear program.

And for the first time today, the U.S. accused China of conducting a secret nuclear test just one day after letting

the final nuclear arms-controlled treaty with Russia expire.

Nick Schifrin's been covering both stories and joins us now.

So, Nick, let's start with the U.S. and Iran.

What do we know about how those talks went today?

Well, the Trump administration has provided no readout at the moment.

But in the lead-up to these talks, we heard from Secretary

of State Marco Rubio and the top negotiator Steve Whitkoff that Iran must not make any nuclear

fuel domestically, must restrict the range of its ballistic missiles, must end its support for

proxy groups, and account for highly enriched uranium that has been missing since last summer

strikes. Today, the U.S. held indirect talks.

You see Wittkoff there with the president's son-in-law, Jared Kushner,

meaning Oman's foreign minister, who then met with Iran's foreign minister, Abas Aranqi,

who said the talks focused on nuclear weapons and were a, quote, good start.

We were able to exchange our viewpoints, to express our concerns and our interests for a possible deal between the two sides on our nuclear question.

Aranji said there would be a new round of talks, no confirmation of that from the U.S. side, which for the first time included the top U.S. military commander from the Middle East, a reminder omina of President Trump's threats against Iran and that military build-up still in the region. So what do the experts tell you all of that means for the possibility of an actual deal? Well, that's the question I put to Kareem Sadrupur of the Carnegie Endowment for International

Peace.

He is very skeptical of any deal of Iran's nuclear program, missile program, or support for

proxies, including Hezbollah and Hamas.

The Iranian regime still seems so intent on defying the United States, and they fear that if they give in to pressure,

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