LONDON Secretary of State Hillary Clinton said that nearly 1,000 people had been killed in a crackdown on pro-democracy demonstrators in Syria and called on President Bashar al-Assad to halt the violence.
"This cruelty must end and the legitimate aspirations of the Syrian people must be honored," Clinton said during a news conference with British counterpart William Hague.
"Foreign Secretary Hague and I are both absolutely consistent with our message to the Assad government," she added.
"Stop the killings, the beatings, the arrests, release all political prisoners and detainees. Begin to respond to the demands that are upon you for a process of credible and inclusive democratic change," she said, speaking shortly before U.S. President Barack Obama begins a state visit to Britain.
The European Union earlier imposed sanctions on Assad and other senior officials, raising pressure on his government to end weeks of violence against protesters.
It followed the United States which last week extended sanctions to Assad and six senior officials.
"President Assad faces a choice. He can lead the transition to democracy ... or he can, as President Obama said on Thursday, get out of the way," Clinton said.
"But there is no doubt that if he does not begin to lead that process his regime will face continuing and increasing pressure and isolation."
Clinton said the United States was "dismayed" at Yemeni President Ali Abdullah Saleh's refusal to sign a transition agreement that would see him cede power.
"President Saleh has agreed on multiple occasions to sign it. Once again he is failing to live up to those promises."
"We urge President Saleh to immediately follow through on his repeated commitments to peacefully transfer power," Clinton added. "This is critical for the peace and security that the Yemeni people are seeking."
Clinton said an attack on a Pakistani naval air force base was "another reminder of the terrible price the Pakistani people have borne in their own struggle against violent extremism."
Troops recaptured the base on Monday after a 16-hour battle with Taliban gunmen who had launched the attack to avenge the killing of al Qaeda leader Osama bin Laden.
"Pakistan has hard choices to make ... It needs international support to deal with political and economic problems and the threats it faces from internal violence," Clinton said.
(Additional reporting by Stefano Ambrogi and Keith Weir, editing by Mark Heinrich)