US President Donald Trump has said Iran will ultimately come to the negotiating table, warning that failure to do so would lead to severe consequences, even as uncertainty persists over stalled diplomatic efforts linked to the ongoing conflict, CBS News reported.

“Well, they’re going to negotiate, and if they don’t, they’re going to see problems like they’ve never seen before,” Trump says in an interview with US radio program The John Fredericks Show, adding that he remains hopeful of a ‘fair deal’ that allows Iran to rebuild while permanently blocking any path to nuclear weapons.

“They’ll have no access to, no chance of having, a nuclear weapon. And we can’t allow that to happen,” he said, describing the issue as critical to global security.

Trump also said the United States had no alternative but to act in Iran. “And I have to say, we had no choice in Iran. It wasn’t like we had a choice. We had to do it,” he said.

US-Iran diplomatic deadlock

His remarks come as Washington and Tehran trade warnings over the future of a fragile ceasefire set to expire Tuesday, with no confirmation on whether US-announced talks in Pakistan will proceed.

The White House has said Vice President JD Vance is prepared to travel to Pakistan for a second round of negotiations aimed at ending the conflict that has destabilized the Middle East and rattled global energy markets.

However, Iranian officials have not confirmed participation, accusing the United States of undermining the truce through what they describe as continued pressure measures, including maritime restrictions. Mohammad Bagher Ghalibaf, who led Iran’s delegation in earlier talks in Islamabad, said Washington was attempting to reshape diplomacy through coercion.

“By imposing a blockade and violating the ceasefire, Trump wants to turn this negotiating table into a surrender table or justify renewed hostilities, as he sees fit,” Ghalibaf said on X. “We do not accept negotiations under the shadow of threats, and in the last two weeks we have been preparing to show new cards on the battlefield.”

Regional flashpoints widen

Iran’s Revolutionary Guards separately warned they would target vessels attempting to pass through the Strait of Hormuz without authorization, further raising tensions in a key global shipping route.

Trump, in separate interviews, said Iran was expected to attend the Pakistan talks and warned of escalation if diplomacy collapsed. “We agreed to be there,” he told PBS News, adding that if the ceasefire expired, “then lots of bombs start going off.”

He also told Bloomberg News it was “highly unlikely” the truce would be extended beyond its current timeframe. While the ceasefire is formally due to expire overnight Tuesday Tehran time, Trump indicated it could run until Wednesday evening Washington time, adding to confusion over the timeline.

Financial markets reacted cautiously, with oil prices easing and equities rising on hopes that diplomacy could prevent further escalation and reopen the Strait of Hormuz, a critical global energy route.

Despite a relative return to normality in parts of Tehran during the truce, residents described continued uncertainty. “Let’s see what happens by Tuesday,” a 30-year-old doctor told AFP on condition of anonymity. Another resident, Saghar, 39, said economic pressure remained severe. “The economy is horrible,” she said.

Meanwhile, regional tensions continue to widen. A separate ceasefire between Israel and Lebanon, announced Friday and involving Hezbollah, remains fragile amid continued warnings from Israel’s military over alleged violations in southern Lebanon.

Israel and Lebanon are expected to hold a second round of indirect talks in Washington on Thursday, according to a US State Department official, even as sporadic violence persists. The UN Security Council on Monday condemned the killing of a French peacekeeper in Lebanon, an incident Paris has blamed on Hezbollah.