Jordan has pledged to begin executing fighters on death row at dawn as part of an "earth-shattering" response to the burning alive of one of its fighter pilots by the Islamic State of Iraq and the Levant (ISIL) group.

Just hours after a video emerged online on Tuesday purporting to show First-Lieutenant Moaz al-Kassasbeh engulfed in flames, a security official said executions would begin at daybreak on Wednesday.

Sajida al-Rishawi, a would-be Iraqi female suicide bomber, was named as the first scheduled to go to the gallows.

Jordanian security sources told Al Jazeera's Nisreen el-Shamayleh that Rishawi would be executed early on Wednesday in response to Kassasbeh.

"The death sentence will be carried out on a group of jihadists, starting with Rishawi, as well as Iraqi al-Qaeda operative Ziad al-Karbouli and others who attacked Jordan's interests," a official told AFP news agency.

Five other individuals on death row could also be executed.

The convicts have already been reportedly moved to al-Suwaqa Jail, where executions in Jordan are typically carried out, a family member of one of the convicts told our correspondent.

'Earth-shattering response'

King Abdullah II, who was visiting Washington DC as the video came to light, recorded a televised address to his shocked and outraged nation.

Abdulla, who was once in the military himself, described Kassasbeh as a hero and pledged to take the battle to ISIL fighters, who have executed several captives on camera in recent months, provoking worldwide revulsion.

"Jordan's response will be earth-shattering," Mohammed Momani, information minister, said on television, while the army and government pledged to avenge Kassasbeh's murder.

"Whoever doubted the unity of the Jordanian people, we will prove them wrong."

Who is Moaz al-Kassasbeh?

US President Barack Obama, who hosted Abdullah in an Oval Office meeting, led widespread international condemnation of the latest murder, decrying the "cowardice and depravity" of ISIL.

"The president and King Abdullah reaffirmed that the vile murder of this brave Jordanian will only serve to steel the international community's resolve to destroy ISIL," a US National Security Council spokesperson said after the White House meeting.

The Obama administration had earlier reaffirmed its intention to give Jordan $3bn in security aid over the next three years.

Kassasbeh was captured in December when his F-16 fighter jet crashed over northern Syria on a mission that was part of the US-led coalition air campaign against ISIL.

Jordanian state television suggested he was killed on January 3, before ISIL offered to spare his life and free a Japanese journalist in return for Rishawi's release.

The country's military has officially informed Kassasbeh's family of his death, Al Jazeera's el-Shamayleh reported from Amman on Tuesday.

International condemnation

The White House would not speculate on whether the video was released to coincide with Abdullah's visit to Washington.

David Cameron, UK prime minister, called the murder "sickening", while Ban Ki-moon, UN secretary-general, labelled it an "appalling act".

The release of the video came after ISIL beheaded two Japanese hostages within a week.

Shinzo Abe, Japan's prime minister, condemned Kassasbeh's murder as "unforgivable".

Speaking to Al Jazeera, Abdel Bari Atwan, a Middle East analyst, said that if proven true, the killing of Kassasbeh was "unprecedented".

"It's a very clear message and they are trying to show maximum brutality," he said, adding that ISIL was not interested in negotiations.

"They are looking to terrorise."

The highly choreographed 22-minute footage shows Kassasbeh at a table recounting coalition operations against ISIL, with flags from the various Western and Arab countries in the alliance projected in the background.

It then shows Kassasbeh dressed in an orange jumpsuit and surrounded by armed and masked ISIL fighters in camouflage.

It cuts to him standing inside a cage and apparently soaked in petrol before a masked fighter uses a torch to light a trail of flame that runs to the cage and burns him alive.

The video also offered rewards for the killing of other "crusader" pilots.

Source: Al Jazeera and agencies