US and Iran accelerate rhetoric as peace talks stall

The United States and Iran have intensified their war of words as the deadline for a fragile ceasefire approaches, with both sides raising the stakes for a second attempt at a peace deal.

Mohammad Berger Ghalibaf, the speaker of Iran’s parliament, appeared to pick up steam on Tuesday in a social media post, accusing US President Donald Trump of “setting up a siege and violating the ceasefire” and trying to turn negotiations into “a table of surrender or to justify new warmongering.”

Ghalibaf also suggested that Iran holds new influence in the conflict. “Over the past two weeks, we have been preparing to reveal new cards to the battlefield,” Ghalibaf did not elaborate. “We will not engage in negotiations hidden behind threats,” he added.

These comments became sharper after President Trump once again threatened to attack Iran with overwhelming military force if a deal is not reached and said there would be “a lot of bombs going off.”

The status of further peace talks and other key details of the current relations between the belligerent powers are becoming increasingly uncertain, with President Trump oscillating between resuming his sword-wielding rhetoric and suggesting that Washington is open to additional negotiations with Iran.

“This is our last chance to reach a deal before the cease-fire expires,” former U.S. Ambassador to Oman Mark Sievers told CNBC’s “Access Middle East” on Monday, warning that the risks are high if President Trump follows through on his threat to resume military hostilities against Iranian power plants and bridges.

The escalation in tensions came as the US delegation was preparing to return to Pakistan for a possible second round of peace talks. A person familiar with the matter told CNBC on Monday morning that the U.S. delegation “plans to go to Islamabad soon.”

The Iranian delegation has not yet left for Islamabad, Reuters reported on Tuesday, citing Iranian state television, contradicting international media reports that the national team was traveling.

The first round of talks in Islamabad, led by Vice President J.D. Vance, Steve Witkoff and US Special Envoy Jared Kushner, ended on April 12 without resolving thorny issues such as Iran’s nuclear program.

The United States and Iran agreed to a two-week ceasefire on the night of April 7th. Tensions have been high throughout the brief period of the temporary ceasefire, with both sides accusing the other of violating its terms.

President Trump said in an interview with Bloomberg on Monday that the cease-fire agreement expires “Wednesday night Washington time,” potentially allowing more time for negotiations. President Trump added that he was unlikely to extend the Iranian ceasefire beyond Wednesday and had no intention of opening the Strait of Hormuz until a deal was reached with Tehran.

Asked if he expected fighting to resume immediately if no deal is reached, Trump said: “If we don’t get a deal, I definitely expect it to resume.”

Cornelia Meyer, CEO of Meyer Resources, said developing a diplomatic roadmap, rather than a permanent settlement, was the most practical outcome of the Islamabad talks. “It is too much to expect a real peace deal,” Meyer said, referring to the Iran nuclear deal that took more than two years of negotiations to reach an interim framework in 2015.

Vance, along with officials from the National Security Council, the State Department and the Pentagon, is part of a U.S. delegation heading to Pakistan for talks on Tuesday, according to multiple news outlets.

Alan Eyre, a former senior US diplomat who helped negotiate the 2015 Iran nuclear deal, said US negotiators could be at a disadvantage at the table with Iran’s experienced diplomatic delegation – a team of experts who “know their portfolio” – but the US side lacks comparable expertise in international relations.

Eyre said that unless the US “brings in a team of trusted and competent experts…they are out of the picture,” adding that the “best possible practical outcome” from potential talks would be agreement on general principles and an extension of the ceasefire.

The fate of Iran’s nuclear material will remain a key issue in negotiations. President Trump said Friday that Iran had agreed to transfer its stockpile of highly enriched uranium to the United States, but Iran denied the claim within hours.

In a post on Truth Social late Monday, President Trump reiterated that the U.S.’s Operation Midnight Hammer, a June 2025 attack that targeted three facilities critical to Tehran’s nuclear program, had succeeded in creating “the complete obliteration of a nuclear dust site” and that “excavating it will be a long and difficult process.”

The United States and Iran are also in a serious deadlock in maritime traffic through the Strait of Hormuz, with President Trump vowing to continue blockading Iranian ports and Tehran reasserting military control of the vital sea route. In normal times, the chokepoint is the highway for 20% of the world’s oil and gas transportation.

Tensions in the canal further escalated, with Iran’s Foreign Ministry accusing the US of attacking an Iranian merchant ship and demanding the release of the crew.

Over the weekend, the U.S. Navy fired on and captured an Iranian-flagged cargo ship as it tried to circumvent the blockade. This was the first significant encounter since the beginning of the U.S. blockade. Meanwhile, the Iranian government opened fire on two ships attempting to pass, the latest incident in a vital artery that puts the two countries on a collision course as the clock ticks down in Islamabad.

“Any escalation, especially military action around Hormuz, could trigger a new spike in oil prices and broader risk-off activity,” said Lloyd Chan, senior currency analyst at MUFG Global Markets Research, noting that with the outlook for peace talks uncertain, markets are speculating when energy shipments through the Strait of Hormuz will resume.

—CNBC’s Kevin Breuninger and Sam Meredith contributed to this report.