US President Donald Trump has called for regime change in Iran in a post on his Truth Social account on April 20, signalling Washington's wider war aims as the Pakistan-brokered ceasefire enters its final 48 hours.

"Israel never talked me into the war with Iran, the results of Oct 7th, added to my lifelong opinion that Iran can never have a nuclear weapon, did," Trump wrote. The reference is to the October 7, 2023 Hamas attack on Israel.

Trump compared the situation in Iran to Venezuela, writing that media outlets did not like talking about the results there. "The results in Iran will be amazing - And if Iran's new leaders (Regime Change!) are smart, Iran can have a great and prosperous future!" he wrote.

The post marks the most explicit call by Trump for regime change in Tehran since the war began on February 28, when US-Israeli strikes killed Iran's supreme leader Ayatollah Ali Khamenei and senior military commanders.

Trump also dismissed coverage of the war by what he called fake news pundits and polls, saying 90% of what they said was made up. He said polls were rigged, comparing them to the 2020 presidential election.

The intervention follows similar comments from Trump on April 19 in which he threatened to "knock out every single power plant, and every single bridge, in Iran" if Tehran did not accept a US-proposed deal.

Iran has already rejected Trump's claim that his negotiating team was en route to Islamabad, with state-aligned media reporting that no second round of talks would take place while the US naval blockade on Iranian ports remained in force.

The Pakistan-brokered ceasefire is due to expire on April 22.

Vice President JD Vance had previously framed Washington's position more narrowly, telling Fox News the goal was to ensure Iran could not develop a nuclear weapon. The shift in tone from the president signals a harder line ahead of the ceasefire deadline.

Iran's foreign ministry has not yet responded to Trump's regime change call.

Tehran has separately demanded $270bn in war reparations from the United States and Israel, and has warned that any continuation of the US naval blockade will be treated as a violation of the ceasefire and prompt the closure of the Strait of Hormuz to hostile shipping.

The regime change rhetoric also conflicts with the position that Pakistani mediators have set out in recent days. Pakistan's army chief Field Marshal Asim Munir has been holding talks in Tehran since April 15 and has reportedly made a breakthrough on outstanding issues including the duration of any Iranian uranium enrichment freeze.