Iran's Supreme Leader, Mojtaba Khamenei, has said that avenging his slain father and predecessor, Ali Khamenei, was "the demand of the nation" and "must certainly" be carried out.
The remarks came in a message delivered during funeral ceremonies for the late supreme leader, according to Iran's state-run broadcaster IRIB.
"We pledge to avenge your innocent blood and all the martyrs of these two wars from the criminal and dishonourable murderers," Mojtaba Khamenei said in the message.
"This matter depends neither on my personal existence nor on that of other officials. Whether we are present or not, it will come to pass."
Ali Khamenei was buried Thursday at the Imam Reza Shrine in the northeastern Iranian city of Mashhad, bringing a week of funeral ceremonies to a close.
He was killed in US-Israeli strikes on Iran that began on February 28 and were followed by Iranian retaliatory attacks.
According to a Thursday report by The Wall Street Journal, Israel recently shared intelligence with the US alleging that Iran had developed a new plan to assassinate US President Donald Trump.
In a Friday post on his Truth Social platform, Trump threatened to launch "thousands of missiles" at Iran if it attempted to assassinate him.
In June, Tehran and Washington signed a Pakistan-brokered memorandum of understanding aimed at ending the war that began in late February and paving the way for a lasting peace agreement.
The memorandum called for an immediate end to fighting on all fronts, the lifting of the US naval blockade on Iran, and the reopening of the Strait of Hormuz.
Despite the agreement, the two sides exchanged attacks this week over the passage of commercial traffic through the Strait of Hormuz.
The US struck targets in Iran, which responded by targeting US assets across the region.
