The U.S. special envoy leading the negotiations with Iran on its nuclear program said that if a fourth round of talks with the Islamic Republic in Oman on Sunday are not productive, "then they won't continue, and we'll have to take a different route."

Steve Witkoff, who also is senior adviser and assistant to President Donald Trump, said the U.S. will not accept a bad deal. The fourth round of talks had been scheduled for May 3 in Rome but were postponed.

"That's correct," Witkoff told Breitbart in a story published Friday. "And look, we didn't think that the talks last week were going to be productive because we needed to get to certain understandings with them, and hopefully, this Sunday they will be productive. Hopefully, that means they will continue those talks. If they are not productive on Sunday, then they won't continue, and we'll have to take a different route."

Witkoff said the U.S. will not allow Iran to maintain a uranium enrichment program, which had been a criticism of the 2015 nuclear deal reached during the Obama administration from which Trump withdrew the U.S. in his first term. The United Nations International Atomic Energy Agency reported in February that Iran has 605.8 pounds of uranium enriched to 60% fissile purity, up from 203.9 pounds since the agency's last report in November. It is close to the 90% enrichment needed for weapons-grade use.

"We've stated our position," Witkoff said. "The Iranians cannot have a bomb. They have stated back that they don't want one. So, we're going to, for the purposes of this discussion, take them at their word that that's actually how they feel. If that's how they feel, then their enrichment facilities have to be dismantled. They cannot have centrifuges. They have to downblend all of their fuel that they have there and send it to a faraway place — and they have to convert to a civil program if they want to run a civil program.

"Now, they have a civil reactor actually in the state of Iran — it's called Bushehr. They have no enrichment capability at this place and if we take them at their word, why not just turn all the rest of their facilities just like Bushehr? ... If they believe in that program, they ought to expand it if they want to. An enrichment program can never exist in the state of Iran ever again. That's our red line. No enrichment. That means dismantlement, it means no weaponization, and it means that Natanz, Fordow, and Isfahan— those are their three enrichment facilities — have to be dismantled."

Witkoff's trip to Oman comes ahead of Trump's scheduled visit to Saudi Arabia, Qatar, and the United Arab Emirates next week, the president's first trip to the Middle East in his second term.

Witkoff added he believes it would be "unwise" for the Iranians to "test President Trump," and he believes "they have no choice" but to accept the U.S. terms for denuclearization. He said the talks are focused exclusively on the nuclear issue, a change from the first Trump administration, which tried to deal widely with Iran's support for terrorist proxies in the region such as Hamas, Hezbollah, and the Houthis.

"Do we think they need to stop enabling Hamas, Hezbollah, the Houthis, and pulling back from being a provocateur?" Witkoff asked. "We do believe that. That's a secondary discussion. Do we think that they should not be supplying weapons to people we consider to be our enemies? We believe that. But again, we don't want to confuse the nuclear discussion because that to us is the existential issue. That's the issue that needs to be solved today and quickly."

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