Only yesterday, the Libyan rebels were advancing westwards toward Muammar Qaddafi's hometown of Sirte, aided by coalition airstrikes against regime forces. But the opposition's momentum appears to have stalled on Tuesday, as Qaddafi's troops retook the towns of Nawfaliyah and Bin Jawad and pursued the retreating rebels to Ras Lanuf, according to Al Jazeera (in the photo above, rebels flee from Bin Jawad on the back of a truck amidst machine gun fire and mortars). The Associated Press reports that some rebels yelled "Sarkozy, where are you?" as they escaped, in reference to French President Nicolas Sarkozy, who has been one of the most ardent proponents of airstrikes against Qaddafi's forces.

The AP says the coalition may have refrained from airstrikes in Bin Jawwad because of overcast skies. "Without air strikes it appears the rebels are not able to hold ground or make advances," Reuters asserts. "The battle around Sirte ... will show if the rebels have reached their limit." Fierce fighting persists in the beseiged western city of Misrata as well.

The setback comes as 40 governments and international organizations--including representatives from the U.S and its European allies, the U.N., NATO, the African Union, and the Arab League--gather in London to discuss the situation in Libya. The British and Italians have floated plans for Qaddafi to slip into exile, while U.S. Secretary of State Hillary Clinton stated that the operation in Libya will continue until Qaddafi "complies" with the U.N. resolution authorizing military intervention. In an interview with CBS earlier today, U.N. ambassador Susan Rice indicated that the U.S. had not ruled out arming the rebels.

The rebels, for their part, have issued a two-page memorandum outlining their vision for a democratic Libya. In a letter to world leaders on Tuesday, Qaddafi declared that Western powers, in backing the rebels, were supporting al Qaeda and killing hundreds of Libyans in a "brutal and unjust attack."