The joint addresses, taped on Tuesday while Mr. Bush and Blair wrapped up their war summit in Northern Ireland, was being aired by the U.S. military as part of a news and information program televised to the Iraqi people.
"You will be free — free to build a better life instead of building more palaces for Saddam and his sons," Mr. Bush said, according to excerpts released by the White House and Blair's office.
Mr. Bush said Iraqis will soon be "free to pursue economic prosperity without the hardship of economic sanctions. Free to travel and free to speak your mind. Free to join in the political affairs of Iraq."
"And all the people who make up your country — Kurds, Shia, Turkomens, Sunnis and others — will be free of the terrible persecution that so many have endured," the president said.
Blair, in his message for the new station called "Towards Freedom," told Iraqis that the United States and Britain had not wanted war.
"But in refusing to give up his weapons of mass destruction, Saddam gave us no choice but to act. Now that the war has begun, it will be seen through to the end," he said.
The station will broadcast from a U.S. C-130 Hercules aircraft circling in the skies over Iraq, beaming five hours of programming to the former Iraqi state TV terrestrial channel, Blair's office said.
The broadcast — which was to be aired at 6 p.m. Baghdad time Thursday — was part of an administration campaign to convince Iraqis and the rest of the Arab world that U.S. troops are not a hostile invasion force. There is still widespread opposition to the war throughout much of the world.
The remarks came a day after Baghdad fell into coalition hands and much of Iraq was being overtaken by British and U.S. forces.
"The long era of fear and cruelty is ending," the president said. "The government of Iraq and the future of your country will soon belong to you."
The U.S.-led campaign has placed huge emphasis on the public face of the war.
U.S. Central Command has held daily briefings in a $1.5 million media center in Qatar, where daily assertions of the campaign's purpose and U.S. troops' compassion are supplemented by films of smiling civilians and pinpoint bombing.
The U.S. has also been dropping millions of leaflets and broadcast on several radio stations and one television station since before the start of the war. These broadcasts have provided Iraqis with both instructions and the rational for the war.