Wailing supporters of Hezbollah take to the streets across the Middle East after Iran called on all Muslims to join the cause as Israel claims hit on leader Nasrallah 'stopped another October 7'

Wailing supporters of Hezbollah have taken to the streets around the world to grieve and condemn Israel following news of the death of leader Hassan Nasrallah.

Demonstrators gathered in Beirut and Tehran with posters of the late Shia cleric after Hezbollah confirmed his death today.

Iran has led international condemnation for the killing, claimed by Israel after heavy bombardment of Hezbollah headquarters in Beirut on Friday.

Iran's Supreme Leader pledged that 'all regional resistance forces' would support the terrorist group as the country demanded a 'strong' response to the attack.

In his first comments since Israel claimed to have killed Nasrallah, Ayatollah Ali Khamenei said, 'it is the duty of all Muslims to stand by the people of Lebanon and Hezbollah' against the 'occupier, evil and suppressor' regime of Israel. 

Hezbollah, a proxy group propped up by Iran, received outpourings of support from its allies in the Middle East upon news of the death of its secretary-general.

Iran's Supreme Leader pledged that 'all regional resistance forces' would support the group as the country demanded a 'strong' response to the attack.

In his first comments since Israel claimed to have killed Nasrallah, Ayatollah Ali Khamenei said; 'It is the duty of all Muslims to stand by the people of Lebanon and Hezbollah' against the 'occupier, evil and suppressor' regime of Israel. 

In a statement read on state TV, he added that 'all regional resistance forces' support and stand beside Hezbollah. 

Iran's First Vice President Mohammad Reza Aref said Saturday that the killing of Hezbollah chief Hassan Nasrallah in an air strike in the Lebanese capital will bring about Israel's 'destruction'. 

'We warn the leaders of the occupying regime that the unjust bloodshed... especially of Hezbollah's secretary general, martyr Seyyed Hassan Nasrallah, will bring about their destruction,' Iran's ISNA news agency quoted Aref as saying. 

Tensions are expected to escalate with the reported death of a senior general in Iran's Revolutionary Guards Corps, alongside Nasrallah.

General Abbas Nilforoushan, deputy commander of Guards operations, 'was killed in Israel's attack on Lebanon that assassinated the Hezbollah chief,' said the official IRNA news agency, giving no further details. 

And Iran Air has cancelled all flights to Beirut until further notice, the airline's spokesman told local media including the Tasnim news agency on Saturday. 

Sources from with Iran have said they are in constant contact with Hezbollah and other regional proxy groups to determine the next step.

Yemen's Houthis said today that the killing of Nasrallah would strengthen their determination to confront 'the Israeli enemy'.

'The martyrdom of... Hassan Nasrallah will increase the flame of sacrifice, the heat of enthusiasm, the strength of resolve,' said a statement from the leadership council of the Iran-backed Huthi rebels, vowing to achieve 'victory and the demise of the Israeli enemy'.

'The resistance will not be broken, and the Jihadist spirit of the Mujahideen brothers in Lebanon and on all fronts of support will grow stronger and bigger.' 

Other Shia communities aligned with the Iranian regime's ideology or Hezbollah's role in Lebanon have been slowly amassing support for confrontation with Israel in recent days.

Iraq declared three days of mourning in light of Nasrallah's death, on Saturday. 

The Iraqi Resistance Coordination Committee, a group comprised of Iranian-backed Iraqi militias, convened last Sunday to discuss possible action over Israel's operations in Lebanon.

'American interests in Iraq and the region will be legitimate targets for the resistance,' the group warned.

The discussion heard that the Aqaba-Basra oil pipeline could drag Iraq towards normalisation with Israel.

The group has previously claimed responsibility for bombing areas in Israel and US bases across the Middle East over the war in Gaza, per Middle East Monitor. 

Iraqi volunteers in predominantly Shiite Basra also queued to register their names in support of Hezbollah following a call from the Jihad and Construction Movement on Friday.

Israel, meanwhile, quickly defended its actions in Lebanon this afternoon as its allies reiterated calls for de-escalation.

The IDF defended their ongoing strikes into Lebanon, claiming Hezbollah was planning its 'own October 7'.

Spokesperson Daniel Hagari said they took out the commander when he was in Hezbollah's central headquarters. 

He said: 'Hassan Nasrallah had the blood of thousands of men, women, children on his hands. Israeli, Jews. Jews across the world. Lebanese. Americans. British. French. Syrians, and other countless victims across the middle east and beyond.'

He continued: 'Hezbollah has openly declared that it has a plan to carry out its own October 7 massacre on Israels northern border, but even in a larger scale. Hezbollah has been planning to do this in northern Israel, what Hamas did in southern Israel on October 7 - invade Israel, infiltrate communities and massacre innocent civilians.

'Hassan Nasrallah, the leader of an evil terrorist organisation, the senior terrorist eliminated with him, and the central headquarters were a legitimate military target under international law.'

Hagari added that Israel had tried to 'minimise' casualties while Hezbollah used civilians as 'human shields', saying that their war is 'not with the Lebanese people'.

Israel's allies overseas have been critical of operations in Lebanon, with dozens killed and thousands wounded.

France and the US have been trying to hash out a three week ceasefire deal, as yet dismissed by Israel.

Hezbollah did not comment on the proposals.

Britain continues to advise against travel to Lebanon, urging people to find routes home.