Thousands of people have convened in the Qatari capital of Doha to hold a funeral prayer for Hamas chief Ismail Haniyeh who was assassinated by the Israeli regime two days earlier.

Large crowds on Friday attended Haniyeh's funeral prayer at Imam Muhammad bin Abdul Wahhab Mosque, the largest mosque in Qatar, amid heavy security measures where participants were searched and phones were prohibited during the service.

The attendees included dozens of foreign dignitaries and representatives from Palestinian groups and factions, including senior Fatah figure Mahmoud al-Aloul.

Fatah, Hamas and several other Palestinian factions signed a unity agreement in Beijing last week for a post-war framework in Gaza.

Iran’s vice-president Mohammad-Reza Aref, heading an Iranian delegation, is in Qatar to attend the ceremonies.

After the service, Haniyeh was laid to rest at a cemetery in Lusail, north of Doha.

A funeral procession and prayer were held for Haniyeh in Tehran on Thursday.

Leader of the Islamic Revolution Ayatollah Sayyed Ali Khamenei led the funeral prayers for Haniyeh and his security guard.

Haniyeh, who was in the Iranian capital to attend the swearing-in ceremony of Iran's newly-elected President Masoud Pezeshkian, was assassinated along with his bodyguard, in an Israeli attack on his residence in northern Tehran early on Wednesday.

On Wednesday, Ayatollah Khamenei warned the Israeli regime of a 'harsh response' for the assassination of Haniyeh, saying it is the Islamic Republic's duty to avenge the blood of the Palestinian resistance leader.

“The criminal and terrorist Zionist regime martyred our dear guest in our homeland and left us bereaved, but it also set the ground for a harsh punishment for itself,” the Leader said.