The US president has extended the truce indefinitely until Tehran presents a "unified proposal" to end the conflict

US President Donald Trump has extended the ceasefire with Iran just hours before the fragile truce was set to expire, but vowed to maintain the naval blockade, touting it as leverage to force Tehran to make a deal.

"I have directed our Military to continue the Blockade and, in all other respects, remain ready and able, and will therefore extend the Ceasefire until such time as their proposal is submitted, and discussions are concluded, one way or the other," Trump wrote on Truth Social on Tuesday.

Earlier on Tuesday, Vice-President JD Vance had been expected to lead the US delegation in Islamabad, alongside Trump envoys Steve Witkoff and Jared Kushner. However, the trip was put on hold after Iranian officials said the talks were pointless as long as Washington maintained its "bullying".

The US president later claimed that Washington would not lift the blockade because "if we do that, there can never be a Deal with Iran, unless we blow up the rest of their Country, their leaders included!"

Here are the latest developments:

• The two-week ceasefire brokered by Pakistan was set to expire on Wednesday, after a first round of talks in Islamabad failed to produce a breakthrough and Trump moved ahead with a US naval blockade of Iranian ports.

• Iranian parliament speaker Mohammad Bagher Ghalibaf accused Trump of trying to turn talks "into a table of surrender or to justify renewed warmongering." President Masoud Pezeshkian said Iranians "will not bow to coercion," while foreign minister Seyed Abbas Araghchi called the blockade of Iranian ports "an act of war and thus a violation of the ceasefire."

• Separate 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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