Iraq's fugitive vice president on Sunday called for an urgent neutral inquiry into the death of his bodyguard, who was allegedly tortured while in custody.

Vice President Tareq Al-Hashemi, a Sunni the authorities have accused of running death squads, said his lawyers had been restricted access to the investigation against him and that the "situation in Iraq has become intolerable."

Hashemi alleges that his bodyguard Amir Sarbut Zaidan Al-Batawi, who died in custody earlier this month, was tortured, and has released photographs which he says support the claims.

Security forces and judicial officials say Batawi died of kidney failure.

Human Rights Watch, meanwhile, has called for a criminal investigation into the death of the 33-year-old father-of-three.

"I ask all human rights related organisations in Iraq to take urgent actions by sending (a) neutral and specialised committee to examine the body medically and to identify the cause of death," Hashemi said in a televised speech delivered in English.

"I also ask security and judicial authorities in Iraq to provide an explanation for what happened."

He said his lawyers had not been allowed to witness investigation hearings, and when they were given access to minutes of the hearing, judges barred them from taking notes or making copies.

"I beseech (the) international community to take rapid action to rectify (the) disastrous situation and status related to human rights, as the situation in Iraq has become intolerable," Hashemi said.

A senior Iraqi general and a judicial spokesman have said Batawi died of kidney failure and other conditions after refusing treatment, and suggested photographs released by Hashemi's office apparently showing Batawi's body bearing signs of abuse were digitally manipulated.

In December, shortly after US troops completed their withdrawal from Iraq, the country's Shia-led authorities issued an arrest warrant for Hashemi on terror charges, sparking a protracted political crisis.

Hashemi, who has been in Iraq's autonomous Kurdistan region for the duration of the row, says the allegations are politically motivated, and Kurdish officials have refused to hand him over to the central government.