(CNN) -- [Breaking news update at 11:50 p.m. Thursday]
The United States respects the vote by the British parliament not to participate in a potential military action against Syria, U.S. Secretary of Defense Chuck Hagel said Friday.
"Every nation has a responsibility to make their own decisions, and we respect that of any nation," he told journalists in Manila, the Philippines.
In spite of the British decision, it remains the goal of the Obama administration that any decision be "an international collaboration," he said.
[Original story, posted at 10:36 p.m. Thursday]
(CNN) The United States may have to take action against Syria without the support of one of its staunchest allies, U.S. officials said Thursday after British lawmakers voted down a proposal for military action.
Washington will continue to consult with Britain, but "President Obama's decision-making will be guided by what is in the best interests of the United States," National Security Council spokeswoman Caitlin Hayden said in a statement issued Thursday evening.
The reaction followed news the House of Commons rebuffed Prime Minister David Cameron's call for a strong response to claims Syria used chemical weapons against its own people, raising questions about what, if any, timeline the United States may follow for a possible strike.
Obama has not spelled out what steps the United States will take in response to last week's reported attack against civilians in a Damascus suburb, allegedly leaving hundreds dead.
"He believes that there are core interests at stake for the United States and that countries who violate international norms regarding chemical weapons need to be held accountable," Hayden said.
Unilateral action was "a possibility" following the results of the late-night Parliament vote in London, a senior U.S. official, speaking on condition of anonymity, told CNN.
"We care what they think. We value the process. But we're going to make the decision we need to make," the official said.
The vote among UK lawmakers came after a long day of debate, and it appeared to catch Cameron and his supporters by surprise.
For days, the prime minister has been sounding a call for action, lending support to talk of a U.S.- or Western-led strike against Syria.
"I strongly believe in the need for a tough response to the use of chemical weapons, but I also believe in respecting the will of this House of Commons," the prime minister said.
"I get that and the government will act accordingly," he said.
The head of the opposition Labour Party, Ed Miliband, called Cameron's call for action "cavalier and reckless."
"I think today the House of Commons spoke for the British people who said they didn't want a rush to war, and I was determined we learned the lessons of Iraq and I'm glad we've made the prime minister see sense this evening," he told Press Association.
At the United Nations, a closed-door Security Council meeting ended with no agreement on a resolution to address the growing crisis in Syria, a Western diplomat told CNN's Nick Paton Walsh on condition of anonymity.
"It was clear there was no meeting of minds, and no agreement on the text. It is clear that our approaches are very different and we are taking stock (of the next steps)," the diplomat said of the session, which was called by Syria's longtime ally, Russia.
The members of the Security Council expect U.N. weapons inspectors to brief Secretary-General Ban Ki-moon shortly after they depart Syria on Saturday. Ban, in turn, will swiftly brief the Security Council on the findings, the diplomat said.
China, which along with Russia has staunchly opposed any military intervention in Syria, called for U.N. weapons inspectors to be allowed to complete their investigation.
"China calls on parties concerned to exercise restraints and calmness, adhering to the right track of political solution," Foreign Minister Wang Yi said in a statement.
Britain's Joint Intelligence Committee has concluded it was "highly likely" that Syrian government forces used poison gas outside Damascus last week in an attack that killed at least 350 people, according to a summary of the committee's findings released Thursday.
Speaking in the House of Commons before the vote, Cameron said failure to respond would undo "decades of painstaking work" to prevent such weapons from being unleashed.