crisis in syria. President obama, weighing his options right now. Congress has been briefed. And white house officials now saying that the surprise vote in great britain is not going to stop the u.S.... See More
crisis in syria. President obama, weighing his options right now. Congress has been briefed. And white house officials now saying that the surprise vote in great britain is not going to stop the u.S. From acting. Preparations for a strike taking place right now. We have full coverage starting with abc's jim avila, who is at the white house with the reaction to that stunning vote in parliament last night. Reporter: Good morning, elizabeth. Overnight, just as the president's people were briefing congress on their case against syria, telling the senators and the congresspeople, even if america has to act alone, america has to respond. Just before the white house began its briefing, stunning news from america's staunchest ally. Britain is out. Parliament reacted the prime minister's motion to intervene. And voted against any action against syria. The british parliament, reflecting the views of the british people. Does not want to see british military reaction. I get that. And the government will act accordingly. Reporter: Now, president obama must respond to syria's chemical attack on its own people alone. Over night, the administration admitted disappointment. But vowed to act on its own. Promising to release an intelligence briefing to the public today, justifying action. BUT SENATOR john McCain says the president isn't ready to go far enough. There's no policy. There's no strategy. And there's no end game here. Until we get one, you're going to see this kind of confusion. And to announce that any action we take would not be in good regime change, to me, is incomprehensible. Reporter: Once that intelligence report is released, and that is expected today, and the u.N. Inspectors leave area, you can expect the window for a possible american military attack to open.
This transcript has been automatically generated and may not be 100% accurate.