An urgent meeting will be held soon in Iran between Qatar's Minister of State for Defense Khalid al-Attiyah, Commander of the Iranian Revolutionary Guard Corps (IRGC) Mohammad Ali Jafari, and representatives of Hezbollah and Houthi rebels, according to informed sources.
Mr Hadi's forces, trying to take advantage of the collapse of the alliance, announced they would march on Sanaa.
The Saudi-led coalition has been hitting Sanaa with air strikes for months, and a fresh wave on Monday targeted areas near Sanaa International Airport and the interior ministry, both under Houthi control, residents and an airport source said.
"I appeal to the leader Saleh to show more wisdom and maturity. and not to heed incitement calls", Abdel-Malek al-Houthi said in a speech on the group's Al-Masirah TV, adding that his group was ready to sit down for arbitration and abide by any ruling.
Witnesses say that fighting has subsided in the Yemeni capital Sanaa hours after the announcement of the death of Yemen's former president Ali Abdullah Saleh.More news: Twitter reactions to the Patriots' 23-3 win over the Buffalo Bills
Two of Saleh's associates have confirmed and a third official from the government of Yemen's internationally recognized president, Abed Rabbo Mansour Hadi, has also confirmed. But he recently switched his alliance to Saudi Arabia, which has led a three-year bombing campaign against the Houthis in Yemen and implemented a blockade of Yemeni ports.
Mr Saleh ruled Yemen for more than 30 years.
The rebel alliance splintered last week, setting off heavy clashes between the Houthis and Saleh's forces.
Yemen's war has killed more than 10,000 people since 2015, displaced more than two million people, and caused a cholera outbreak infecting almost one million people. Iran has denied the accusations. "Ambulances and medical teams can not access the injured and people can not go outside to buy food and other necessities", Stephane Dujarric, a United Nations spokesman in Yemen, said in a statement on Sunday.
It was a grisly end for a figure who was able to rule the impoverished and unstable country for more than three decades and remained a powerhouse even after he was ousted in a 2011 Arab Spring uprising. He remained in the country, however, and continued to wield political power from behind the scenes.