Iran's ambassador to Pakistan, Reza Amiri Moghadam, announced a "step forward" in negotiations with the United States on April 7, suggesting Pakistani mediation had helped avert an immediate escalation.

"As of now, a step forward from critical, sensitive stage ... In the next stage, respect and comity should replace rethorics and redundancy. Stay more tuned...," Moghadam wrote on X.

Pakistan has emerged as the primary intermediary between Washington and Tehran since the war began on February 28. Islamabad hosted foreign ministers from Turkey, Saudi Arabia and Egypt on March 29 in a coordinated push to end the hostilities, following an earlier consultation in Riyadh on March 19 in which the same regional powers began aligning their approach. 

The ambassador had earlier said that "Pakistan's positive and constructive efforts in the framework of goodwill and mediation to end the war are approaching a critical and sensitive stage."

The comments came as US President Donald Trump told Fox News that "intensive negotiations" were under way, though he declined to provide details, hours before his self-imposed deadline for Iran to reopen the Strait of Hormuz or face strikes on power plants and bridges.

Pakistani Prime Minister Shehbaz Sharif called on Trump to extend the deadline by two weeks and urged Iran to reopen the strait for the same period as a goodwill gesture. Sharif wrote on X that diplomatic efforts "are progressing steadily, strongly and powerfully and have the potential to lead to substantive results in the near future."

Pakistan's army chief, Field Marshal Asim Munir, has been in contact "all night long" with US Vice President JD Vance, Special Envoy Steve Witkoff and Iranian Foreign Minister Abbas Araghchi, according to local media. 

Trump said he would be briefed on Sharif's proposal shortly.

The diplomatic flurry came on day 39 of the war, with US forces striking more than 50 military targets on Iran's Kharg Island overnight and Israel acknowledging attacks on Iranian railways and bridges.

Under the emerging proposal, tentatively dubbed the "Islamabad Accord", a ceasefire would take effect immediately, reopening the Strait of Hormuz, with 15 to 20 days given to finalise a broader settlement. The final agreement is expected to include Iranian commitments not to pursue nuclear weapons in exchange for sanctions relief and the release of frozen assets. 

Crude oil has surged past $115 a barrel amid Iran's continued closure of the Hormuz strait, through which roughly 20% of global oil passes.