A speaker purported to be the deposed Iraqi leader denounced Iraq's newly formed Governing Council in an audiotape aired on Al-Arabiya satellite television.
The reference to the council, which was formed by U.S. administrators and met for the first time on Sunday, indicated the message was new.
"How can the people benefit from employees named by the foreign occupiers," said the voice on the tape. "What can those named by the foreign occupier offer to the people and the nation other than the will of the occupier."
The tape, which reporters familiar with Saddam's voice said sounded authentic, aired for about five minutes. There was no way to independently authenticate that the voice was the ousted Iraqi leader's.
Thursday was the anniversary of the 1968 Baathist revolution that brought Saddam's political party to power. Saddam himself seized power 11 years later. U.S. commanders have worried that Thursday and other anniversaries in July might spark intensified attacks on American troops.
Rumors have spread quickly among the Iraqi public that Saddam would make some sort of appearance on the anniversary.
In other developments:
"It's very, very important to all of us to make sure that our soldiers, sailors, airmen and Marines know when they're coming home," Abizaid said at a Pentagon news conference.
Before they go home, those troops undoubtedly will face more attacks from former members of Saddam's Baath Party and from terrorist groups who want to derail Iraq's transition to democracy, Abizaid said.
Abizaid's use of the term "guerrilla warfare" was a striking departure for a top military leader. As recently as last week, Defense Secretary Donald H. Rumsfeld and other Pentagon officials refused to use the term.
Midlevel Baath Party operatives have organized themselves into cells of perhaps 10 people. Terrorist groups like the al Qaeda-linked Ansar al-Islam pose another threat to American forces, he said.
"It's low-intensity conflict in our doctrinal terms, but it's war however you describe it," said Abizaid, who took over last week as head of U.S. Central Command.
The military said it had no word early Thursday of fresh attacks on U.S. troops, who have come under increasingly ferocious and frequent attack by suspected Saddam loyalists in recent weeks — reaching an average of 12 attacks a day.
More than 30 U.S. soldiers have been killed in hostile action since Mr. Bush declared an end to major hostilities on May 1. At least 146 have been killed in combat since the start of the Iraq war.
In violence Wednesday, attacks killed a U.S. soldier, an Iraqi girl hit when a grenade was thrown at U.S. troops, and an American-backed Iraqi mayor and his son. Insurgents firing a missile missed a military transport plane landing at Baghdad's airport.
The alleged Saddam message follows another audiotape purportedly from Saddam aired July 5 in which he told Iraqis he is still in the country organizing resistance to the U.S.-led occupation. CIA officials said at the time that the voice was likely Saddam's but they could not be certain because of the recording's poor quality.
The council was "made by the will of the foreigners, therefore it is the servant of the foreigner and not a servant of the people."
"The occupier has occupied in order to weaken Iraq and destroy its will, and therefore, anything issued by occupation is to weaken Iraq. The only solution … is a jihad (holy war) to resist the occupation," said the voice.