"The current worry... is that Assad will be able to move everything into hiding [before a strike]," Jabri said. "Then the strikes won't matter at all."
Jabri also spoke to the fear shared by the FSA that the regime will lash out viciously following a possible U.S. military strike.
"My colleagues in Damascus and Homs and everywhere else are terrified of what the bombing campaign will bring. They spent everyday of the past ten days on their toes. Obama's 'tomorrow or next week or next month' bit is a lot harder on them than it is on Assad," Jabri said.
Officially, the spokesman for the Syrian opposition umbrella group, the Syrian National Coalition, Louay Safi called Obama's decision a "failure of leadership."
On Sunday afternoon, the Coalition released a statement urging coordination with opposition forces.
"The Syrian Coalition believes any possible military action should be carried out in conjunction with an effort to arm the Free Syrian Army. This will be vital in restraining Assad and ending the killing," the coalition said in a statement.
The head of the Coalition, Ahmed Aljarba, is expected to address the Arab League foreign ministers tonight in Cairo.
The League's deputy chief, Ahmed Ben Helli announced an emergency session "in light of rapid developments in the Syria situation." The permanent members are meeting Sunday afternoon behind closed doors and the minister level talks are slated to begin at 6p.m. local (12p.m. EDT).
Last week, the 22-nation bloc called the Aug. 21 attacks a "horrible crime carried out with internationally prohibited chemical weapons" and placed the "entire responsibility" on the Assad regime. However, the permanent members stopped short of calling for military action outside of U.N. framework.
Israel Remains On Alert
Israeli Prime Minister Benjamin Netanyahu remained largely mum on Syria this morning, reiterating that Israel is ready for "any possible scenario."
"Israel is serene and self-confident," Netanyahu said in today's cabinet meeting.
"Israel's citizens know well that we are prepared for any possible scenario. And Israel's citizens should also know that our enemies have very good reasons not to test our power and not to test our might," he added.
But op-eds in Israeli media this morning accused Obama of getting "cold feet."
"The assessment is that Obama is buying time in hope of finding a diplomatic route that will allow for the attack to be called off altogether," said Israel's Yedioth Ahronoth daily newspaper.
Chairman of the Jewish Home party, Naftali Bennet struck a harsher tone, saying "The international stammering and vacillation over Syria proves, yet again, that Israel can trust in none but itself," according to Reuters.
Roy Keider, the CEO of Israel's Reut Institute told ABC News that "President Obama's decision to consult Congress shows hesitancy or lack of decisiveness" in Israeli eyes.
"Knowing that Israel could be the one who actually suffers the consequences of a US strike, I believe that most Israelis will support such a move in order to deter Syria from using non-conventional weapons and to signal to Iran that US means business when it comes to non-conventional weapons," Keider added.
Israeli Radio reported Sunday morning that the Israeli Defense Forces remain on high alert and reserve troops called up last week have yet to be released.
On Friday, the IDF deployed an Iron Dome battery in the Tel Aviv area facing north. Iron Dome batteries were also deployed in Haifa, Ashkelon, and Eilat and additional batteries are ready to be moved as needed, according to Israeli media.
ABC News' Molly Hunter reported from Jerusalem, Alex Marquardt and Terry Moran both contributed reporting from Beirut.