The White House says President Barack Obama has decided there will be a response to the Syrian government's alleged use of chemical weapons and is now working with his national security team to determine what it will be.
Spokesman Jay Carney says there was "no doubt" that poison gas was used during an August 21 attack in suburban Damascus.
In a Tuesday briefing, he said there was very little doubt the Syrian regime was responsible for the attack, which he said was a "flagrant violation" of international laws.
Carney also said that later this week the U.S. would release an intelligence report on the poison gas attack.
The Syrian government has denied launching any chemical attacks and has blamed rebels for last's week attack that left hundreds dead.
Earlier Tuesday, U.S. Defense Secretary Chuck Hagel says the American military is ready to act if President Obama orders retaliation against the Syrian regime for its alleged use of chemical weapons.
Hagel told the BBC on Tuesday that the U.S. military had "moved assets in place" and would be able to "fulfill and comply" with any option Mr. Obama wishes to take.
News reports say the U.S. and several other Western powers are considering a limited, targeted response to to Damascus' alleged use of chemical weapons to punish Syrian President Bashar al-Assad.
A U.N. team is currently in Syria to investigate the alleged use of chemical weapons but its mission was delayed Tuesday due to security concerns.
Stephen Zunes, a professor of Middle East studies at the University of San Francisco, says while there is pressure on the United States to take military action, there are limits to what strikes can accomplish.
"The impulse is quite understandable, but on a practical level it does not seem that it would make such a difference in terms of the military balance given that the rebel forces are divided into literally hundreds of different militia, some of which are as anti-Western or more so than the regime."
Michael O'Hanlon, a Brookings Institution foreign policy and security expert, says Mr. Obama had been reluctant to step up U.S. engagement in Syria. However, he told Alhurra TV that Mr. Assad had pushed the U.S. and the international community "one step too far."
"What President Assad has done is to force President Obama to consider options that previously that he had not been willing to consider and I think President Assad is going to realize that he made a very tragic mistake, not only for the hundreds of people killed but even for the good of his own regime."
The U.S. on Tuesday postponed a meeting with Russian officials scheduled for later this week to discuss the situation in Syria.
Russia and China have repeatedly blocked actions at the United Nations to impose sanctions on the Syrian government for assaults on the civilian population during the civil war.