Pakistan's army chief Field Marshal Asim Munir was due in Tehran Thursday for fresh talks aimed at salvaging stalled efforts to end the US-Israeli war on Iran, as President Donald Trump warned that negotiations were on the "borderline" between a deal and renewed strikes.US Secretary of State Marco Rubio however, voiced cautious hope of progress. "I believe the Pakistanis will be travelling to Tehran today. So hopefully that'll advance this further," he told reporters.Iran's ISNA news agency said Munir's visit was aimed at continuing "talks and consultations" with Iranian authorities, without providing further details. Three sources told Reuters the army chief — a powerful figure with a growing role in Pakistan's foreign relations — was possibly heading to the Iranian capital for a new round of mediation."We're speaking to all the various groups in Iran to streamline communication and so things pick up pace," one source familiar with the negotiations said. "Trump's patience running thin is a concern, but we're working on the pace at which messages are relayed from each side."Pakistan hosted in April the only direct negotiations between US and Iranian officials since the war began on February 28. Munir was at the centre of the action during that round, greeting both delegations on their arrival and displaying remarkable bonhomie with US Vice President JD Vance. But the talks ultimately did not lead to a breakthrough, with Iran accusing the US of making "excessive demands".A ceasefire on April 8 halted the fighting launched weeks earlier by the US and Israel, but no lasting peace agreement has been reached. "It's right on the borderline, believe me," Trump told reporters on Wednesday. "If we don't get the right answers, it goes very quickly. We're all ready to go." He said a deal could come "very quickly" or "in a few days", but warned Tehran would have to provide "100 percent good answers".The deepest splits remain over Iran's stockpile of near-weapons-grade enriched uranium and control of the Strait of Hormuz. Trump vowed Washington would not allow Iran to retain the material. "We will get it. We don't need it, we don't want it. We'll probably destroy it after we get it, but we're not going to let them have it," he said.Supreme Leader Ayatollah Mojtaba Khamenei has, however, issued a directive that the uranium should not be sent abroad, two senior Iranian sources said. Top officials in Tehran believe shipping the material out would leave Iran more vulnerable to future US-Israeli strikes. The sources said "feasible formulas" remained, including diluting the stockpile under IAEA supervision.Tehran's chief negotiator Mohammad Baqer Qalibaf accused Washington of preparing fresh attacks, warning of a "forceful response". Iran's foreign ministry spokesman Esmaeil Baqaei said Tehran was studying the latest US points while reiterating demands for the release of frozen assets and an end to the US naval blockade.The impasse continues to batter the global economy. The Strait of Hormuz, which normally carries about a fifth of the world's oil and LNG, remains largely shut, with Iran allowing only a trickle of vessels through under a new toll regime. US crude rose 3.22% to $101.42 a barrel, while Brent climbed to $107.71. The International Energy Agency warned the market could enter the "red zone" in July and August. The UN Food and Agriculture Organisation cautioned that a prolonged closure could trigger "a severe global food price crisis".Rubio also criticised Nato allies for refusing to back Trump's campaign. "He's not asking them to commit troops...But they refuse to do anything. We were very upset about that."
