"He is distraught and depressed," Allawi told the Arabic daily al-Hayat in an interview from London where the Iraqi leader is currently on a visit.
"Saddam and his cronies are not the all-powerful men that they are sometimes portrayed as in the media," said Allawi, whose government took over power from the US occupation in late June.
"Saddam transmitted a message to me begging for mercy. He said they had been working for the public interest and their goal was not to do harm."
But Allawi said his response was: "It is for the courts to decide."
Still insisting he is Iraq's lawful leader, Saddam Hussein eats US army meals for breakfast, reads the Quran and tends plants outside his cell in one of his former palaces near Baghdad, according to a New York Times report.
Saddam wears plastic sandals and an Arab dishdasha robe and is permitted three hours daily exercise in the courtyard outside his cell, where he places white painted stones around plants he tends.
Eleven close associates who appeared with him in court on 1 July are allowed to exercise with him and to play chess, dominoes, poker and backgammon together, the paper said.
Saddam could go on trial as early
Members of the group still address one another by the titles they had in the Saddam Hussein government, Iraqi Human Rights Minister in the interim government Bakhtiar Amin told the Times.
Saddam was charged with seven crimes, including the massacre of Kurds and Shia Muslims and the invasion of Kuwait at his first court appearance in Baghdad in July.
A defiant Saddam insisted at the hearing he was still the legitimate president of Iraq, defended the 1990 invasion of Kuwait and gave a lecture on points of law.
He had been captured in a hole near his northern hometown of Tikrit in December, eight months after US-led invasion forces toppled his regime.
But Allawi painted a different picture of Saddam before the hearing.
Saddam still insists he is Iraq's
As he was being taken to the court, Saddam was "visibly trembling. He thought things would go as they had done in his time and that he was being taken for execution", he said.
"He only calmed down when he saw the judges and the press and television correspondents."
In an interview on Sunday with US television network ABC, Allawi said Saddam could go to trial as early as next month, along with a number of his henchmen.
"I don't think it will take a long time, because the evidence against him is ... overwhelming. So we hope justice will be served."
Asked if he meant the death penalty, Allawi only said: "The death penalty has been restored in Iraq."
It had been suspended by the US-led occupation authority after the fall of Saddam.
In his interview with al-Hayat, Allawi also mentioned he had survived four assassination attempts since his interim government came to power in June.
The last was just five days ago when his guards became suspicious of a car outside Baghdad's Green Zone compound housing the government and the US and other embassies.