BAGHDAD, Iraq -- Saddam Hussein urged Iraqis to embrace "brotherly coexistence" and not to hate U.S.-led foreign troops in a goodbye letter posted on a Web site Wednesday, a day after Iraq's highest court upheld his death sentence.

The court ordered him hanged within 30 days.

A top government official, meanwhile, said Saddam's execution could proceed without the approval of Iraq's president, meaning there were no more legal obstacles to sending the deposed dictator to the gallows.

One of Saddam's attorneys, Issam Ghazzawi, confirmed to The Associated Press in Jordan that the Internet letter was authentic, saying it was written by Saddam on Nov. 5 -- the day he was convicted by an Iraqi tribunal for ordering the 1982 killings of 148 Shiite Muslims in Dujail.

"I call on you not to hate because hate does not leave space for a person to be fair and it makes you blind and closes all doors of thinking," said the letter, which was written in Arabic and translated by the AP.

"I also call on you not to hate the people of the other countries that attacked us," it added, referring to the invasion that toppled his regime nearly four years ago.

Against the backdrop of sectarian killings that have dragged Sunni Arabs and Shiite Muslims into civil warfare over the past year, Saddam urged his countrymen to "remember that God has enabled you to become an example of love, forgiveness and brotherly coexistence."

But he also voiced support for the Sunni Arab-dominated insurgency, saying: "Long live jihad and the mujahedeen." He urged Iraqis to be patient and rely on God's help in fighting "against the unjust nations."

Saddam said he was giving his life for his country as part of that struggle. "Here, I offer my soul to God as a sacrifice, and if he wants, he will send it to heaven with the martyrs," he said.

Despite his calls for conciliation among Iraqis, Saddam's legacy is brutal. He put suspected foes to death without trial, oppressed Kurds and Shiites, waged war on Iran and twice fought U.S.-led armies. He left an impoverished nation now gripped by sectarian bloodshed and an insurgency against the U.S. presence.

Violence struck Baghdad again Wednesday, with a car bomb killing eight civilians and wounding 10 near an Iraqi army checkpoint. Four more civilians died in a mortar attack in a Shiite neighborhood, and police found the bodies of 51 apparent victims of sectarian killings.

Questions had arisen about whether the appeals court's ruling needed to be approved by the Iraqi presidency, which customarily signs off on death sentences.

Busho Ibrahim, deputy justice minister, said it wasn't necessary. "According to the legal provisions of the court, there is no need for the approval of the presidency," he said.

A spokesman for President Jalal Talabani acknowledged the legal argument that the execution could go ahead without ratification by the president, who has expressed opposition to the death penalty.

"Some people believe there is no need for his approval," spokesman Hiwa Osman said. "We still have to hear from the court as to how the procedure can be carried out."

An official from Prime Minister Nouri al-Maliki's Dawa Party, speaking on condition of anonymity because he was not authorized to talk to the media, said that "the government wants Saddam executed as soon as possible."

Another official close to al-Maliki, who also refused to be quoted by name, said the execution would take place before the end of the 30-day period.

Saddam will remain in a U.S. military prison near the airport, Camp Cropper, until the day of the execution, at which point he will be handed over to Iraqi authorities, the official said.

Ghazzawi, the defense lawyer, said the letter by Saddam was released Tuesday and published Wednesday on the Web site of Saddam's former Baath Party.

The deposed leader said he was writing the letter because his lawyers had told him the Iraqi High Tribunal that tried his case would give him an opportunity to say a final word.

"But that court and its chief judge did not give us the chance to say a word, and issued its verdict without explanation and read out the sentence -- dictated by the invaders -- without presenting the evidence," Saddam wrote.

"Dear faithful people," he added, "I say goodbye to you, but I will be with the merciful God who helps those who take refuge in him and who will never disappoint any honest believer."

Some Saddam loyalists threatened to retaliate if he is executed, warning in a posting on the same Web site that they would target U.S. interests.

"The Baath and the resistance are determined to retaliate, with all means and everywhere, to harm America and its interests if it commits this crime," the statement said, referring to Baath fighters as "the resistance."

The Baath Party was disbanded after U.S.-led forces overthrew Saddam in 2003. The Web site is believed to be run from Yemen, where a number of exiled members of the party are based.

The appeals court also affirmed death sentences for two of Saddam's co-defendants, including his half brother. It ruled life imprisonment for a third was too lenient and demanded the lower court also sentence him to death.

Some Iraqis said Saddam should be hanged immediately, but others feared Iraq's bloodletting could escalate if the former dictator is executed at a time when sectarian attacks are already on the rise.

"Executing him now is dangerous. The situation is very bad. Things need to be calmer," said Saadia Mohamed Majed, a 60-year-old Shiite in Baghdad who wants the penalty to be postponed for at least three years.

Saddam is in the midst of another trial, charged with genocide and other crimes during a 1987-88 military crackdown on Kurds in northern Iraq. An estimated 180,000 Kurds died during the operation. That trial was adjourned until Jan. 8, but experts have said the trial of Saddam's co-defendants is likely to continue even if he is executed.

The U.S. command reported three American military deaths Wednesday, bringing the U.S. death toll for December to 93 in one of the bloodiest months for U.S. troops this year. Some 105 soldiers and Marines were killed in October, according to an AP count.

"This has been a difficult month for coalition forces, and the month is not over yet," a military spokesman, Maj. Gen. William Caldwell, said.

Two Latvian soldiers were also killed and three were wounded when a roadside bomb exploded under their Humvee, the Latvian Defense Ministry said. It was unclear where the incident took place, but Latvia has about 130 soldiers serving in Diwaniyah, 80 miles south of Baghdad.

A top aide to the radical Shiite cleric Muqtada al-Sadr was killed in a raid by U.S. troops Wednesday in the Shiite holy city of Najaf, an Iraqi lawmaker said.

The U.S. military said the death occurred during a joint operation by American and Iraqi troops. It described the man, Sahib al-Amiri, as a criminal involved in the use of roadside bombs.