Hopes for reviving Iran-US peace efforts through Pakistan dimmed again on Saturday after US President Donald Trump canceled the planned Islamabad visit of his envoys Steve Witkoff and Jared Kushner, shortly after Iranian Foreign Minister Seyed Abbas Araghchi wrapped up talks with Pakistan's leadership and left for Oman.

Earlier, the White House had announced that the two key negotiators would travel to Pakistan, with White House Press Secretary Karoline Leavitt describing Pakistan as an "incredible" mediator throughout the process.

However, late Saturday, Trump called off the visit, saying, "We have all the cards. They can call us anytime they want, but you're not going to be making any more 18-hour flights to sit around talking about nothing."

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The cancellation came after Tehran had already made clear that no direct talks with US officials would take place in Islamabad unless its conditions were addressed first.

An Iranian delegation led by Araghchi arrived in Islamabad late Friday night for consultations on regional developments and possible diplomatic efforts to end the conflict that began on Feb 28 with US-Israeli strikes on Tehran and several other Iranian cities.

Iran's Foreign Ministry spokesperson denied reports of any planned meeting with US officials in Pakistan, while Iranian media said Araghchi would only consult with the Pakistani side and use Islamabad as a channel to convey Iran's considerations regarding ending the conflict.

Pakistani and Iranian officials held multiple rounds of meetings on Friday and Saturday and focused on proposals related to potential future negotiations between Tehran and Washington, Pakistani sources told Xinhua.

Araghchi met Prime Minister Shehbaz Sharif on Saturday in Islamabad. Deputy Prime Minister and Foreign Minister Ishaq Dar and Chief of Army Staff Field Marshal Asim Munir also attended the nearly two-hour meeting, according to the Prime Minister's Office.

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Sharif emphasized the importance of dialogue and diplomacy for peace and stability in the region and beyond, the PM's Office said.

Earlier, Araghchi also held talks with Munir and conveyed Iran's views regarding the end of the military conflict, the ceasefire with the United States and Israel, and broader regional stability, according to Iranian media reports.

Pakistani officials, acting as mediators, conveyed messages from Washington during the discussions, after which the Iranian delegation presented its responses and key demands, sources said.

A late-night meeting between the two sides upon Araghchi's arrival focused on Tehran's preconditions before any direct engagement with Washington, including lifting the US naval blockade and releasing Iranian ships and crew seized by the US side.

The Iranian side said it would remain engaged to help shape a future diplomatic path and appreciated Pakistan's "untiring and sincere efforts" to promote peace and stability, the sources added.

At the same time, Tehran hardened its public messaging over the blockade.

Iran's main military command, Khatam al-Anbiya Central Headquarters, warned on Saturday that it would react if the United States continued what it called "blockade, banditry and piracy" in the region, referring to the US naval blockade on the Strait of Hormuz and recent actions against Iran-bound vessels.

The command said Iran's armed forces were prepared to inflict "more severe damage" if the United States and Israel repeated what it called aggression, while maintaining control over the strategic waterway.

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The renewed tensions came after a ceasefire was reached on April 8 following 40 days of fighting, and after the first round of Iran-US talks in Islamabad on April 11-12 failed to produce an agreement.

Iran had earlier declined to attend the expected second round of talks in Pakistan, citing the continued US blockade and what it described as excessive American demands.

Although Pakistani mediation remains active and sources said Araghchi could return to Islamabad if ongoing contacts make progress, Saturday's developments suggested that the path toward renewed negotiations remains uncertain, with both sides still far apart on the core conditions for resuming talks.