A United States diplomatic delegation is travelling to Islamabad, Pakistan, for a second round of direct negotiations with Iran, President Donald Trump announced on Sunday, even as the two countries remain locked in a dangerous standoff over the Strait of Hormuz — the narrow waterway linking the Persian Gulf to the Arabian Sea through which roughly one-fifth of the world's oil normally passes. The announcement came with a stark warning: if Iran does not accept Washington's deal, Trump said, "the United States is going to knock out every single power plant, and every single bridge, in Iran."

The delegation, reported to include Trump envoy Steve Witkoff and the president's son-in-law Jared Kushner, is expected to arrive in Islamabad on Monday. Vice President JD Vance, who led the first round of talks in Pakistan's capital on April 11–12, was also reported by US media to be heading the team, though conflicting signals from the White House left his participation unclear. Pakistan, which brokered the current two-week ceasefire between Washington and Tehran — set to expire on April 22 — has been engaged in intensive diplomacy to bring both sides back to the table. Security forces in Islamabad were already tightening arrangements ahead of the talks, and Pakistan's army chief had recently visited Tehran carrying new US proposals, which Iran's Supreme National Security Council said were "under review."

The backdrop to these talks is a rapidly deteriorating situation in the strait. Iran briefly reopened the waterway on Friday following a separate 10-day ceasefire between Israel and Hezbollah, the Lebanese armed group aligned with Tehran. But after Trump confirmed the US naval blockade of Iranian ports — which began on April 14 — would remain until a final deal is signed, Iran's Islamic Revolutionary Guard Corps (IRGC) reversed course and reimposed strict control. IRGC gunboats subsequently fired on vessels attempting to pass, including ships flagged to India, prompting New Delhi to summon the Iranian ambassador. Shipping traffic through the gulf came to a near-standstill. Iran's parliamentary speaker and chief negotiator, Mohammad Bagher Ghalibaf, was blunt: "It is impossible for others to pass through the Strait of Hormuz while we cannot." He acknowledged progress had been made in talks but said "many gaps and some fundamental points remain."

Beyond the strait, several core issues continue to divide the two sides. The fate of Iran's nuclear enrichment programme remains the most contentious: Trump has claimed the US will recover Iran's stockpile of approximately 440 kilograms of enriched uranium, which he has referred to as "nuclear dust," left at sites struck during earlier US-Israeli operations. Iran flatly rejected handing over the material, with a deputy foreign minister calling the idea "a nonstarter." Iran's President Masoud Pezeshkian pushed back against broader US demands, asking: "Who is he to deprive a nation of its rights?" The status of Iran's regional allies — including Hezbollah and armed factions in Iraq and Yemen — also remains unresolved.

With the ceasefire's expiry days away, the stakes could hardly be higher. The war, now in its eighth week since US and Israeli strikes on Iran began on February 28, has killed at least 3,000 people in Iran, more than 2,290 in Lebanon, and dozens of others across the region including US and Israeli military personnel. Analysts warn that the current exchange of threats and military pressure risks sliding into renewed large-scale conflict. Pakistan's mediation role — geographically and diplomatically positioned between the two adversaries — may represent the last realistic off-ramp before the ceasefire collapses entirely.