John McCain and other lawmakers called Tuesday for the U.S. to consider arming the Syrian opposition, as new videos emerged purporting to show the bloody aftermath of the weekend's massacre in the Syrian city of Homs.
"The bloodletting has got to stop," McCain, the Republican senator from Arizona, said.
The Obama administration, though, pushed back on the idea -- stressing instead the options of humanitarian assistance and increased international pressure.
"We don't think more arms into Syria is the answer," State Department spokeswoman Victoria Nuland. "We think the answer is to get to a national democratic dialogue, for the violence to stop, for the regime's tanks to come out of the cities and then for monitors to be able to go back in."
The debate in Washington comes in the wake of two major clashes over the weekend -- one at the United Nations Security Council, the other in Homs. At the Security Council, Russia and China blocked an Arab League proposal calling for Syrian President Bashar Assad to step down. The Obama administration condemned the veto.
In Homs, Assad's forces were blamed for an assault that activists say killed more than 200 people. Startling and graphic YouTube videos began to surface by Tuesday claiming to show on-the-scene footage from the aftermath of the attack.
Some videos showed the fighting from a distance, with smoke billowing from the burning buildings of the Homs skyline.
Others showed what appeared to be makeshift medical quarters, where victims were spread out on the floors for treatment or attempted resuscitation.
One video, which was aired on Al Jazeera, appeared to show bloodied children, one of them crying out. Another panned to show several wounded victims, though it was not always clear whether the individuals shown were alive.
McCain, who supported U.S. intervention in Libya, told Fox News that "all options must be on the table" with regard to Syria -- even when Fox News inquired about the use of drones.
McCain, though, said U.S. troops should not be sent into Syria.
The Obama administration has pushed back against the prospect of outright military intervention. And without a U.N. resolution, the U.S. may be further deterred from any deep coordination with the Syrian rebels. The administration on Monday announced that it was closing its embassy in Syria.
Nuland said Tuesday that the administration would "never take anything off the table" but stressed that arming the rebels is not the "right answer" at this point.
He said the administration is "exploring the possibility of providing humanitarian aid to Syrians" and continues to try to work with other nations to "ratchet up the pressure, ratchet up the isolation on Assad and his regime."
Carney said the Assad regime is "not going to last."
"Ultimately, it needs to result in Assad ceasing the violence, stopping the brutality and allowing for a transition supported by the Syrian people," Carney said.
Fox News' Trish Turner contributed to this report.