Donald Trump has threatened Tehran with overwhelming military force, saying "lots of bombs [will] start going off" if no deal is reached

Iranian and US negotiators are set to arrive in Pakistan for a second round of talks as a shaky ceasefire is due to expire.

According to sources cited by both US and Iranian media, the delegations are due to arrive simultaneously in Islamabad on Tuesday evening. Vice President J.D. Vance will reportedly lead the US side, joined by President Donald Trump's envoys Steve Witkoff and Jared Kushner, while Iran's team will be headed by Parliament Speaker Mohammad Bagher Ghalibaf.

A two-week ceasefire brokered by Pakistan earlier this month is set to expire on Wednesday, after a first round of talks in Islamabad produced no breakthrough and Trump moved ahead with a US military blockade of Iranian ports - a step Tehran has labeled a violation of the truce.

On Monday, Trump resumed his trademark saber-rattling, telling PBS that "lots of bombs [will] start going off" if no deal is reached and making clear he has no intention of extending the ceasefire. He also insisted the blockade will remain in place until Tehran folds.

Iran has struck a defiant tone. Ghalibaf warned Tehran is ready to "reveal new cards on the battlefield," rejecting any negotiations conducted "under the shadow of threats." He accused Trump of trying to turn talks into "a table of surrender," adding Iran has spent the past two weeks preparing new military options. President Masoud Pezeshkian echoed the message, calling US conduct "non-constructive and contradictory" and insisting Iranians "will not bow to coercion."

Despite the rhetoric, Axios reported that Pakistani, Egyptian, and Turkish mediators pushed Tehran to attend, with Iran's team reportedly receiving a green light from the supreme leader, Mojtaba Khamenei, late on Monday.

Here are the latest developments:

• Tensions escalated further after the US Navy seized an Iranian cargo ship, the Touska, for allegedly breaching the blockade - a move Tehran branded "armed maritime piracy" and threatened to retaliate over.

• Iran's IRIB state broadcaster said none of its negotiators had yet departed for Islamabad.

• Talks between Israel and Lebanon are reportedly set for Thursday to discuss extending their ceasefire, due to expire on Sunday.

• The Middle East conflict has triggered what IEA chief Fatih Birol called "the biggest" energy crisis in history.

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