Syrian forces kept up a relentless campaign against the country's two-month uprising, using tanks to shell a besieged border town as President Barack Obama called on Syria's president to lead his country to democracy or "get out of the way".
President Bashar Assad has taken pains to portray confidence and a steely determination in recent days amid signs that his brutal crackdown is terrifying the population into submission.
The regime's crackdown on dissent, which has killed more than 850 people, continued ahead of another round of protests planned for after Friday prayers.
Syria's state-run news agency also condemned new US sanctions, saying they "did not and will not affect Syria's independent choices and steadfastness".
The Syrian army shelled the town of Talkalakh overnight Wednesday sparking gun battles that killed at least eight people, bringing the death toll to 34 since the military sealed off the border town on Saturday and moved in tanks and troops.
Syrians fleeing to Lebanon in recent days have described horrific scenes of execution-style slayings and bodies in the streets in Talkalakh.
Last week, mass arrests and heavy security kept crowds below previous levels seen during the uprising, suggesting Assad's sweeping campaign of intimidation is working.
Obama yesterday called for the first time for the leader of Syria to embrace democracy or "get out of the way," though without specifically demanding his removal.
The Syrian government "has chosen the path of murder and the mass arrests of its citizens," Mr Obama said, praising the Syrian people for their courage in standing up to repression.
Talkalakh, a town of some 70,000 people near the border with Lebanon, is known to be a smuggling area where many residents are armed. It has been a hotbed of dissent during the two-month uprising against Assad's autocratic rule.
The new US sanctions mark the first time they hold Assad personally accountable for actions of his security forces. The European Union, meanwhile, is pushing for a second round of European sanctions that would target Assad.
Syria and its ally in Lebanon, Hezbollah, both alluded to charges that the US is conspiring with Israel.
Hezbollah said the sanctions amount to a settling of accounts with Syria because of its support for Hezbollah, the Palestinian people and its refusal to take dictates from America.
The Syrian government called the sanctions "one in a series of sanctions imposed by the US administration against the Syrian people as part of US regional policies serving Israel".
The statements come against the backdrop of Obama's speech, in which he said "too many leaders in the region tried to direct their people's grievances elsewhere. The West was blamed as the source of all ills, a half century after the end of colonialism. Antagonism toward Israel became the only acceptable outlet for political expression".