Pakistan pressed ahead on Tuesday (Apr 21) with the groundwork for a second round of talks between Iran and the United States in Islamabad as a fragile ceasefire hung in the balance, even though it remained unclear whether Tehran would send a delegation.

Both sides remain dug in rhetorically, with US President Donald Trump warning that "lots of bombs" will "start going off" if there’s no agreement before the ceasefire deadline, which he put as Wednesday, and Iran’s chief negotiator saying that Tehran has "new cards on the battlefield" that have not yet been revealed.

The two-week ceasefire began on Apr 8, and seemed likely to be extended if talks resume as planned. White House officials have said that US Vice President JD Vance would lead the American delegation, but Iran has not said who it might send, with Iranian state television reporting on Tuesday that no delegation has yet departed for the peace talks. 

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