The collapse of diplomatic efforts aimed at securing a U.N. Security Council resolution condemning Syria was expected. The British impediment was not.
The developments came as President Obama warned in a TV interview that chemical weapons "that can have devastating effects could be directed at us" and made clear he is considering limited military action against Syrian President
"I have no interest in any kind of open-ended
How soon such strikes might occur remained unclear after British
On Wednesday, the team visited the eastern Ghouta region northeast of Damascus, the zone that apparently was hit hardest by poison gas before dawn on Aug. 21. Assad's government is suspected of carrying out the attack, which killed hundreds.
U.S. officials, who have said there is already conclusive proof of Syrian government culpability, sought to avoid extending the investigation as a delaying tactic.
Marie Harf, a
In London, Parliament will consider a weaker-than-expected motion Thursday that deplores the use of chemical weapons and says that a humanitarian response might require "military action that is legal, proportionate and focused on saving lives by preventing and deterring further use of Syria's chemical weapons."
It will also say that "every effort" should be made to win a U.N. blessing for any military response. Russia, which is Assad's primary international supporter, made it clear Wednesday that it would not support any Security Council move to censure Syria or sanction military action.
At the U.N., in a meeting of the five permanent members of the Security Council, British representatives had proposed a resolution condemning Syria's use of banned chemical agents and called for "all necessary measures" to respond to it.
But Russia killed the proposal and foreclosed any further discussion, diplomats said.
Harf said U.S. officials would consult other countries about possible military action as well as other options, and "will take appropriate actions to respond in the days ahead."
After a meeting of the group's policymaking arm, NATO Secretary-General
His statement didn't commit NATO to joining a military operation but gave its blessing if one is launched, said Jorge Benitez, an analyst with the Atlantic Council of the United States and editor of the NATOsource blog. "They're saying, 'We support what you're going to do.' "
NATO members signaled fewer misgivings than before other recent U.S.-led interventions. Germany and Poland, which did not support the NATO-led air campaign against
The United States appears likely to have support from France, Britain, Turkey and at least four Persian Gulf states. The Arab League voted Tuesday to condemn Syria's apparent poison gas use but stopped short of supporting military action.
The U.N. special envoy to Syria, Lakhdar Brahimi, told reporters in Geneva that an armed response without U.N. approval would be illegal under international law. He also said the Obama administration had not shared its evidence on the Assad government's alleged role in the attack.
"We will be very, very, very interested to hear from them what this evidence they have is," Brahimi said.
U.S. officials are expected to release an intelligence report as early as Thursday that they believe shows Syrian commanders ordered the use of chemical weapons.
On Capitol Hill, House Speaker
Boehner urged Obama to "personally make the case to the American people and Congress for how potential military action will secure American national security interests, preserve America's credibility, deter the future use of chemical weapons and, critically, be a part of our broader policy and strategy."
Assad's government has denied responsibility for the attack, blaming rebels who have fought to oust him from power since early 2011.