Mr. Assad, in his first public address since April 16, promoted a process of national dialogue as a path to reform. Opposition leaders have said they wouldn't take part.
Assad supporters were out in force in Damascus, the Syrian capital,which has yet to see sustained, mass antiregime demonstrations. In a central square, thousands of people waved flags and portraits of Mr. Assad, chanting: "We sacrifice ourselves for you, Bashar."
The proregime demonstrations were backed, and possibly organized to some extent, by the government. Mass text messages were sent Monday urging people to march. Syria's state news agency said millions of people across the country were "flocking to the public squares in support of the reform process under the leadership of President Bashar al-Assad."
But almost four months into protests that have polarized Syrian society, Mr. Assad maintains a loyal base among the large merchant families of Damascus and Aleppo, the country's second-largest city. He also commands support among some minorities—including the Christian population—who prefer his autocratic rule over an unknown alternative andthe potential of sectarian strife.
"We have to acknowledge that the regime still can rally a surprising number of people," said an opposition supporter in Damascus.
Mr. Assad in his speech on Monday said it was necessary to protect the country from "saboteurs," a view that appeared to resonate with those who favored security over change.
He also promoted a process of national dialogue in which the government would seek out 100 people to discuss reforms to the electoral law and constitution, which gives the ruling Baath Party a monopoly on political life in Syria. Opposition leaders have said they wouldn't take part while tanks and troops remain in the streets.
Mr. Assad on Tuesday announced a general amnesty for prisoners suffering from terminal illness, for all crimes except drugs and arms smuggling, the state news agency reported. Thousands of people have disappeared or been detained amid the crackdown on protests. It was unclear if the amnesty would result in the release of any of them. Human-rights activists say hundreds were released after an amnesty earlier this month.