Huge crowds have gathered in Tehran for the funeral of Iran's late supreme leader Ali Khamenei, with millions calling for 'revenge' against the US. Khamenei ruled the Islamic republic from 1989 until he was killed aged 86 in an airstrike on the first day of the US-Israeli war with Iran on February 28.Today's service at Tehran's Grand Mosalla complex was led by prominent Shia cleric Ja'far Sobhani, a 97-year-old scholar. It came one day after mourners flooded the streets of Tehran chanting 'death to America!' over Khamenei's killing. As authorities unveiled the casket containing his body in a glass case, crowds wept and chanted 'our word is one! Revenge! Revenge!' A performer at today's service called for the death of Donald Trump, marking the first, direct call for the US president's death by an emcee at the funeral. Mohammad Rasouli, a poet, drew calls of 'Death to America!' and 'Death to Israel', adding, 'Why is the most b****** man in the world still alive?' in reference to Trump. Khamenei's son and successor Mojtaba Khamenei, who is said to have been wounded in the February 28 attack, has not appeared in public since being named supreme leader and was absent from the funeral prayers. Mourners attend a prayer during a public farewell ceremony today to pay their respects to the late supreme leader Ayatollah Ali Khamenei Iranian women mourn as they take part in a mass prayer for the late Iranian supreme leader People gather next to a large photo tribute to Ali Khamenei this morning for the second day of the funeral Supporters gather at the Grand Mosalla to pray for Iran's slain supreme leader today Iranian women hold flags and put their hands on their chests as they pay their respects among the crowd A woman wears a photo of the late supreme leader on her back for the service today Khamenei's other three sons, Masoud, Mostafa and Meysam, were in attendance. Khamenei's body will today be moved from the Grand Mosalla complex where it is lying in state in preparation for processions through the capital on Monday.The vast religious complex and surrounding streets were packed with mourners this morning. With temperatures set to exceed 35C, supporters carrying Iranian flags and portraits of Khamenei as they made their way to the Grand Mosalla were handed refreshments.President Masoud Pezeshkian attended the ceremony alongside senior officials including parliament speaker and Iran's chief negotiator Mohammad Bagher Ghalibaf. Khamenei's coffin, draped in the Iranian flag and topped with his black turban, was placed alongside the coffins of four relatives also killed in the February strikes, including an infant granddaughter.Authorities have said they expect more than 10 million people to take part in ceremonies in Tehran.After five weeks of intense hostilities, the Middle East war is on hold after a ceasefire and an initial accord with the US. Both Washington and Tehran have warned they are ready to resume fighting at any time.Khamenei's funeral is being viewed outside Iran as a test of support for the government following mass protests before the war in January that rights groups say were quelled by a crackdown that left thousands dead. Crowds are sprayed with mists of water to keep them cool during the heat at the Grand Mosalla complex Prayers were held today over the casket of Iran's late supreme leader Ali Khamenei A woman holds a tissue and appears emotional as she stands among the crowd of mourners Thousands of people stand in the crowd of people who came to pay their respects today Mourners attend a prayer during a public farewell ceremony in Tehran today Hundreds of thousands of Iranians gather at the Imam Khomeini Mosalla to attend the funeral prayer Crowds are sprayed with mists of water to keep them cool during the heat at the Grand Mosalla complex Mourners fill staircases to join the huge crowd of grieving people paying their respects to the late supreme leader 'What is observed today in the emotions, tears, and passionate presence of the people in various scenes is the most telling sign of his position among the Iranian nation and the free people of the world,' Pezeshkian said in a speech yesterday, accusing Israel of acting as a 'destabilising factor' in the Middle East.'Muslims have shown that they will not surrender to oppression and bullying,' he added.Khamenei had long pursued a course of confrontation with the West, and Tehran has for years provided support to anti-US and anti-Israel armed groups around the region, including Palestinian Hamas and Lebanon's Hezbollah.Delegations from both groups met with Foreign Minister Abbas Araghchi yesterday, state media reported, while representatives of Yemen's Houthi rebels and Hamas ally Palestinian Islamic Jihad were also in attendance at the funeral.After Monday's procession, Khamenei's coffin will be moved on Tuesday to Qom, then on Wednesday to neighbouring Iraq, before the burial on Thursday in his northeastern hometown of Mashhad.Significant security measures have been imposed in the capital, and official media has warned attendees of the risk of crowd crushes.Organisers have also taken measures to mitigate a heatwave that may nudge 40C in Tehran over the next few days, with crowds yesterday sprayed with mists of water to keep cool at the Grand Mosalla complex.Three of Khamenei's sons prayed beside his coffin today but Mojtaba, the son who has succeeded him, did not make an appearance.Mostafa, Meysam and Masoud prayed behind the coffins laid out in the vast courtyard.Khamenei's coffin was displayed outdoors yesterday under glass, along with those of his daughter, son-in-law, daughter-in-law and 14-month-old granddaughter. Mojtaba Khamenei's face was disfigured and he suffered a significant injury to one or both legs, people close to his inner circle said.