Last Updated 4:45 p.m. ET
TUNIS, Tunisia - U.S. Secretary of State Hillary Rodham Clinton blasted Russia and China as "despicable" for opposing U.N. Security Council action on Syria, and more than 60 nations began planning a civilian peacekeeping mission to deploy after the Damascus regime halts a brutal crackdown on the opposition.
President Barack Obama said Washington will keep pressuring Syrian President Bashar Assad to stop the "slaughter" of civilians, saying it was imperative that the world unite in condemning the Syrian military onslaught.
"It is time to stop the killing of Syrian citizens by their own government," Mr. Obama said after a conference by a group of nations known as the Friends of Syria concluded in Tunisia.
The move by the group is aimed at jolting Assad and his allies into accepting demands for a democratic transition, even as they are still unwilling to commit to military intervention to end the nearly year-old bloodshed.
While the conference in Tunisia offered nothing other than the threat of increasing isolation and sanctions to compel compliance from Assad, Clinton went on to predict a military coup inside Syria of the kind that ended the old regimes in Egypt and Tunisia.
"We saw this happen in other settings last year, I think it is going to happen in Syria," she told reporters at the end of the meeting. "We also know from many sources that there are people around Assad who are beginning to hedge their bets they didn't sign up to slaughter people."
Clinton said the Syrian regime will have "more blood on its hands" if it doesn't immediately comply with cease-fire demands.
Assad allies Russia and China, which have blocked previous U.N. action on Syria and are eager to head off any repeat of the kind of foreign intervention that happened in Libya, gave no sign they would agree to peacekeepers. Their actions prompted a particularly strong reaction from Clinton.
"It's quite distressing to see two permanent members of the Security Council using their veto while people are being murdered women, children, brave young men houses are being destroyed," she said. "It is just despicable and I ask whose side are they on? They are clearly not on the side of the Syrian people."
In New York on Friday, U.N. deputy spokesman Eduardo del Buey said the secretary-general's office had no immediate response to a call for a peacekeeping mission.
The conference, meeting for the first time as a unified bloc, called on Assad to end the violence immediately and allow humanitarian aid into areas hit by his regime's crackdown. The group pledged to boost relief shipments and set up supply depots along Syria's borders, but it was unclear how it would be distributed without government approval.
The friends, led by the U.S. and European and Arab nations, also vowed to step up ties with the Syrian National Council, an opposition umbrella group. They took a tentative step toward recognition by declaring the council to be "a legitimate representative" of the Syrian people, a possible precursor to calling it "the legitimate representative."
Despite the show of unity, which diplomats said they hoped would impress upon Assad that the end of his family's four-decade autocratic rule is inevitable and at hand, there were signs of division. Some nations argued for arming Assad's foes, while others called for the creation of protected humanitarian corridors to deliver aid.
Neither idea was included in the conference's final document, which instead focused on steps nations should take to tighten the noose on the regime, including boycotting Syrian oil, imposing travel and financial sanctions on Assad's inner circle, and working with the opposition to prepare for a post-Assad Syria, including lucrative commercial deals. It also welcomed the appointment of former U.N. chief Kofi Annan to be a joint U.N.-Arab League special envoy for Syria.
On the sanctions front, France said the European Union would on Monday freeze assets of Syria's national bank held in EU jurisdictions while Clinton vowed that already tough U.S. penalties would be strengthened.
Highlighting the divisions, though, Saudi Arabia called publicly for weapons and ammunition to be sent to the opposition, including the Free Syrian Army, a Turkey-based outfit made up largely of Assad regime defectors.
"I think it's an excellent idea," Saudi Foreign Minister Saud al-Faisal told reporters as he prepared to meet Clinton on the margins of the conference. Asked why, he replied: "Because they have to defend themselves."
Clinton demurred on the question. But on Thursday in London, she said the opposition would eventually find arms from some suppliers if Assad keeps up the relentless assault.
The Obama administration initially opposed arming the opposition but has recently opened the door to the possibility by saying that while a political solution is preferable, other measures may be needed if the onslaught doesn't end.
The Syrian National Council, for its part, said it would be grateful for help in any area.
"We welcome any assistance you might offer, or means to protect our brothers and sisters who are struggling to end the rule of tyranny," council president Burhan Ghalioun told the conference. He laid out the council's goal of a free, democratic Syria free of the "rule of a Mafia family" in which the rights of all would be respected.
Qatari Foreign Minister Hamad Jassim bin Jabr al-Thani, who has been a driving force to unite Arab opinion against the Syrian regime, directly called on Assad to step down. And, together with Turkish Foreign Minister Ahmet Davutoglu, he called for the creation of humanitarian corridors to get aid to embattled citizens.
Tunisian President Moncef Marzouki, the host of the conference who only recently assumed power after his country became the first in the Arab Spring to topple its longtime leader last year, called for an Arab peacekeeping force to ensure stability during an eventual transition.
"We have to respond to the demand of the majority of the Syrian people to get rid of a corrupt, persecuting regime," he said. "We have to stop the bloodshed, but this cannot be through military intervention."
The Friends group recognized this call by giving a green light to U.N. chief Ban Ki-moon to start drawing up plans for such a joint Arab League-U.N. peacekeeping operation that would be comprised of civilian police officers. Ban is expected to begin recruiting possible contributors to the mission and preparing its mandate.
Such an operation would not be a military intervention but would still require authorization from the U.N. Security Council, where it will likely face opposition from veto-wielding members China and Russia, neither of which attended the Tunis conference, and Iran. Russia and Iran are Syria's two biggest military suppliers.
As the conference began, about 200 pro-Assad demonstrators tried to storm the hotel. The protest forced Clinton to be diverted briefly to her hotel.
The protesters, waving Syrian and Tunisian flags, tussled with police and carried signs criticizing Clinton and President Barack Obama. They were driven out of the parking lot by police after about 15 minutes.