The United States is committed to helping the Syrian opposition salvage victory, Secretary of State John F. Kerry said Wednesday, as the Obama administration held crisis talks on whether to shift policy and begin arming the increasingly desperate rebels.

“We are determined to do everything that we can in order to help the opposition to be able to . . . save Syria,” Kerry said. “And that stands.”

President Obama’s top national security aides met at the White House on Wednesday to air options for expanding aid to the rebels after a disastrous battlefield setback last week. Neither Kerry nor White House press secretary Jay Carney would discuss the outcome, but both blamed the widening violence on Syrian President Bashar al-

The “choice of weapons that he has engaged in across the board challenge anybody’s values and standards of human behavior. And we’re going to have to make judgments for ourselves about how we can help the opposition to be able to deal with that,” Kerry said.

That was partly a reference to the British and French contention that they have evidence that Assad has used chemical weapons. Obama has repeatedly said that such a move would be a “red line” triggering U.S. action. France sent its dossier of evidence to Washington a week ago, but the State Department said Wednesday that the United States is not ready to say whether it agrees with the French findings.

As the Syrian conflict enters its third year, it has become increasingly divided along sectarian lines, pitting a largely Sunni opposition against Shiites and Alawites, members of a Shiite-
affiliated sect to which Assad belongs. That shift was evident in the battle for the border town of Qusair, where militants from the Lebanese Shiite movement Hezbollah led the offensive alongside Assad’s troops.

On Tuesday, about 60 civilians and pro-government fighters were killed when rebels stormed a largely Shiite village in eastern Syria, according to the Britain-based Syrian Observatory for Human Rights. Videos released by the activist group showed rebels boasting of burning the houses of “rejectionists,” a derogatory term for Shiites.

The United Nations on Thursday updated its estimate of how many people have been killed in Syria since the conflict began, increasing the death toll from 80,000 to 92,901.. U.N. officials added that the true number could be considerably higher. Kerry has recently said that the death toll could be more than 100,000. The conflict, which began as an uprising inspired by the Arab Spring revolutions, has become an increasingly sectarian civil war that is drawing in other Middle East powers.

Carney played down the sense that emergency talks this week will lead to a quick decision on the Obama administration’s next step.

Obama’s options have always been few and poor in Syria, and any intervention would be a gamble. There is no assurance that U.S. military help would turn the tide for the rebels or drive Assad to the bargaining table in earnest; it might only invite a longer fight that pits the United States directly against Hezbollah and Iran.

The rebel rout at Qusair last week has added urgency to the debate over widening U.S. military support for the opposition, with the rebels saying that they are losing and cannot win without a heavy influx of weapons and other help. Gen. Salim Idriss, commander of the rebel Free Syrian Army’s Supreme Military Council, implored the Obama administration last weekend to provide weapons and air cover ahead of an expected battle for the larger prize of Aleppo.

Despite broad endorsement of Idriss’s military leadership, the administration remains wary of sending arms, concerned that they might be appropriated by the growing numbers of anti-Western Islamist fighters also seeking Assad’s ouster.

Idriss renewed his plea for antitank weapons and ammunition in a Wednesday morning telephone conversation with Sen. Robert P. Casey Jr. (D-Pa.). “The administration has a tough decision to make, but I don’t think there’s a lot of time,” Casey said.

Prospects for a proposed U.N.-sponsored peace conference in Geneva have dimmed with Assad’s military resurgence.

“Our priority remains to see a diplomatic process in Geneva that succeeds in reaching a negotiated end to the conflict,” British Foreign Secretary William Hague said after meeting Kerry for an emergency coordinating session on Syria. “But we will have to be prepared to do more to save lives, to pressure the Assad regime, to negotiate seriously and to prevent the growth of extremism and terrorism if diplomatic efforts are going to succeed.”

There has been no decision by Britain to send arms to the Syrian rebels, Hague said Sunday. Prime Minister David Cameron’s government is split on the issue, with some echoing Obama’s concerns about prolonging the conflict.

Also Wednesday, the Obama administration announced an easing of sanctions on some commercial goods and manufacturing products for rebel-controlled areas of Syria. The blanket ban on the export of many goods that could support the Assad regime will be lifted on a case-by-case basis, the State Department said.

Loveday Morris and Ahmed Ramadan in Beirut contributed to this report.