The Pentagon stated that it deplored what it perceives as an increased use of air power on behalf of the Syrian military against the rebels.
Reuters reports that the Pentagon did not call for a no-fly zone after making clear their distaste. Such a no-fly zone would encompass western air power (probably operating from Turkish Air Force bases and even possibly alongside Turkish military aircraft) establishing control over part of or even all of Syria's air space under the pretext of protecting oppositional elements that are under attack from Syrian military forces. The establishment of such a no-fly zone may require shooting down Syrian interceptors and destroying its missile air defense networks.
George Little the Pentagon spokesman was quoted as saying that the Pentagon has "seen a very troubling and despicable uptick in attacks from the air, perpetrated by the Syrian regime. This is yet another example of their depraved behavior. This needs to stop as does the violence they continue to pursue against their own people."
In a March while testifying to Congress the Defense Secretary Leon Panetta warned that establishing a no-fly-zone over Syria could result in "severe collateral damage," as Syria's air defence systems -- which are reportedly much more qualitative and quantitative than Libya's under Gaddafi -- are located in populated areas.
However there has been renewed speculation (as AFP points out in this report) about implementing such a no-fly zone, the United States has made it official that it has not ruled out any option to bring out the dismantlement of the Assad regime.
White House spokesman Jay Carney has stated that Obama "and his tea have ruled out no option as we try to bring about, with all of our partners and with the Syrian people, the diplomatic transition that is so desperately needed in Syria."
On Saturday whilst in Turkey to discuss the Syrian crisis with Turkey's Foreign Minister Ahmet Davutoglu Mrs. Clinton stated the prospect of a no-fly zone needs "greater in-depth analysis."