Mr. Bush reiterated his call on Syria to remove all of its soldiers and intelligence forces from Lebanon and said the United States was consulting with allies about possible steps if Damascus refuses.
"The Syrians must remove their troops as well as their intelligence services," Mr. Bush said, calling on Syrian President Bashar Assad to comply with U.N. demands for a complete withdrawal.
Mr. Bush's comments came as Syrian soldiers began withdrawing to the Bekaa Valley, near the Syrian border.
But Mr. Bush said pulling back to the Bekaa Valley was not enough.
"That is a half measure," he said. "It is a measure but it's a half measure."
Mr. Bush said he would work with allies to pressure Syria. "The world is speaking now. That's what President Assad must understand. That's not just the Western world that speaks."
Mr. Bush said he was impressed by Saudi Crown Prince Abdullah's admonition to Assad to abide by U.N. demands.
As Mr. Bush spoke, Syrian soldiers in the mountains north and east of Beirut were moving out in trucks from bases they have held for almost three decades. In some instances, Lebanese troops were taking their place were in the midst of the first stage of a pullback from Lebanon.
The Syrians waved at journalists as they loaded supplies, packed up their personal belongings and drove east. One helmeted soldier riding in the back of one truck looked backward down the road, chewing and spitting watermelon seeds.
From a truck hauling a 155mm howitzer artillery cannon, a first lieutenant said, "Some of us are going to Syria and some to the Bekaa."
In Damascus, tens of thousands of people took over the main streets, singing national songs and proclaiming their loyalty to President Bashar Assad. One banner addressed to the president read: "We are all with you, who makes the right decisions."
Thousands of Syria's red, white and black flags with its two green stars streamed in the wind. "We sacrifice our blood and our souls for you, oh Bashar!" chanted marchers in the upscale Mezzeh neighborhood,
"Nobody can get Syria out from Lebanon's heart and mind," a banner read. "No for antagonist pressures against Syria," read another.
The rally came a day after Syria's allies in Lebanon made a thundering show of their strength, with hundreds of thousands turning out for a protest organized by the Shiite Muslim Hezbollah guerrilla group to denounce pressure from the United States, France and the United Nations.
Meanwhile, Lebanon's pro-Syrian prime minister, who was forced to resign last week by opposition protests, was virtually assured of being asked to form the next government after a majority of lawmakers backed him Wednesday.
An unofficial count gave Omar Karami more than half the votes in the 128-member legislature. A formal announcement by President Emile Lahoud, who consulted with legislators Wednesday, may be made as early as Wednesday night or Thursday.
An unofficial count gave Omar Karami more than half the votes in the 128-member legislature.
By early evening, 70 of the 78 legislators -- most of them government loyalists -- who met with Lahoud advised him to reappoint Karami, according to announcements by the legislators as they left the presidential palace.
Opposition lawmakers only sent two representatives and did not put forward a name when they met with Lahoud. Instead, they reiterated their demands for the new government: the complete withdrawal of Syrian troops and intelligence officials from Lebanon, the resignation of Lebanese security officials they deem as negligent and a thorough investigation into the Feb. 14 assassination of former Prime Minister Rafik Hariri.
Re-nominating Karami as prime minister is sure to enrage the opposition, who led weeks of protests against Syria -- including one on Feb. 28 in which more than 25,000 people demanded, and got, the government's resignation. Karami has been leading a caretaker government since then.
But Damascus is eager to keep its hold on the Lebanese leadership as it pulls its forces back to the Bekaa Valley, near the Syrian border, and negotiates with the government in Beirut on the troops' full removal.
The redeployment was the first phase of a plan announced Monday by Assad and Lahoud. The 14,000 Syrian troops in Lebanon are to pull to the eastern Bekaa Valley, then to the border before both sides work out their removal from Lebanon.
Lebanese officials said the pullback would be completed by March 23 and the full withdrawal would come soon after, but gave no dates.