Free Syrian Army fighters are silhouetted as they ride on a tank in the countryside of Kaferzita, Hama, on Sept. 19, 2014. Reuters/Khalil Ashawi

The U.S. is withdrawing its weapons support for the moderate rebel groups it previously backed in northern Syria after they suffered major defeats in Idlib province last week at the hands of an al Qaeda affiliate. Washington is searching for new fighters to prop up, members of the Free Syrian Army said Tuesday.

Meanwhile, after more than three years of war and hundreds of thousands of people dead, President Bashar Assad, the leader that the U.S. onced vowed would fall to opposition forces, remains in power.

It seems "likely that the weapons will stop,” Mohammed Ghanem, a senior political adviser in Washington at the Syrian American Council, a grassroots organization based in Chicago, said. “The situation now in Syria … it's not pretty to be honest with you. We don’t have high hopes.” Ghanem is part of a network of Syrian nonprofit organizations that are working to brief senior U.S. officials in Washington on the situation on the ground in Syria and that advocate for the support of the Syrian opposition.

The Syrian Revolutionary Front (SRF) and the Harakat Hazzm Movement are two major beneficiaries of the U.S. weapons program in Syria that fight under the umbrella of the Free Syrian Army. Both of the groups have suffered major losses in the last several weeks in Syria, overrun by Islamist militant groups like al-Nusra. Syrian opposition members affiliated with the groups, some of whose spokesmen requested anonymity, said U.S. weapons shipments have stopped.

The Department Of Defense told the International Business Times Tuesday that it is currently not working with Harakat Hazzm.

In an interview with International Business Times in October in Istanbul, more than a month before the groups were defeated in Idlib, the leader of the Hazzm movement, Khalid Saleh, said that the anti-armor missiles, known as TOW missiles, that were given to his group by the U.S. had run out.

SRF and Harakat Hazzm were pushed out of Idlib province by al-Nusra, al Qaeda’s offshoot in Syria, last week. Militants fighting with al-Nusra took over the Hazzm movement’s headquarters in Der Sonnbol and seized weapons, including some of the TOW missiles.

The two groups supported by the U.S. and some of its Sunni allies were led by Jamal Maarouf, who is suspected of having fled to Turkey following the fighting in Idlib. Al-Nusra, the group that defeated the U.S.-backed rebels last week, issued a statement Monday declaring its rejection of any factions that support Maarouf. Several dozen Hazzm movement fighters were reported to have joined al-Nusra following its victory in Idlib.

Several videos were published on YouTube over the weekend following the attacks, one of which showed al-Nusra fighters purportedly driving tanks through Idlib with the U.S. weapons they seized from the moderate rebels.

Defense Secretary Chuck Hagel said in a House hearing last week that the U.S. "longer-term effort is to train and equip creadible, moderate Syrian opposition forces," but the U.S. has been arming the moderate rebels in Syria for more than a year; the idea is not new. What is new, Ghanem said, is that the U.S. is thinking about the possibility of arming rebels in southern Syria.

"There is more hope for rebels in the South," Ghanem said. "The South might become the model for Syria." But, he said, the U.S. needs to avoid the mistakes it made with the moderate opposition groups it previously backed.

In the spring of 2013 the U.S. selected groups of rebels fighting with the Free Syrian Army, first through a classified CIA-led program, which was formally announced in August 2013. The program allowed for the transfer of U.S.-made weapons to Turkey via other countries’ aircrafts. The weapons were then driven into Syria by truck. The program was partially funded by Saudi Arabia and other wealthy Sunni states.

Last year, the U.S. ramped up efforts to support the moderate opposition and began training several thousand rebels at a secret base in Jordan. Since then, the rebels have failed to make any significant advances in Syria. In fact, they lost Homs, once dubbed the "heart of the revolution," to the regime in May.

The emergence of the Islamic State, also known as ISIS or ISIL, set the rebels back even further. They had to fight on multiple fronts with little resources and dwindling U.S. support. That lack of U.S. support was one of the main reasons why the moderate rebels failed to stave off al-Nusra in Idlib, according to several opposition activists urging Washington to send more weapons.

"We think that President Obama threw the Syrian opposition under the bus," Ghanem said, adding that U.S. and Turkish officials met last week and proposed the idea of training another 2,000 Syrian rebels but "given how abysmal the situation is in Syria, that seems like a bad joke," he said. It is not clear which moderate rebels would be trained under the new deal.

The U.S. administration’s rhetoric on Syria has changed over time, starting with confident statements in 2011 and again in 2012 that Assad would soon fall. The Syrian moderate opposition, U.S. officials said, represented Syria’s best alternative. In August 2011 Obama said Assad was “on his way out” and that “the balance has shifted.” About one year later, in October 2012, Obama said: “I am confident Assad’s days are numbered.” But now, the U.S. is so focused on defeating ISIS in Iraq that it has all but forgotten about Syria, Ghanem said, pointing to Hagel's testimony last week.

"In Syria, our actions against ISIL are focused on shaping the dynamic in Iraq, which remains the priority of our counter-ISIL strategy. But we are sober about the challenges we face as ISIL exploits the complicated, long-running Syrian conflict,” Hagel said in his testimony. “Because we do not have a partner government to work with, or regular military partners as we do in Iraq, in the near term, our military aims in Syria are limited to isolating and destroying ISIL’s safe havens.” Hagel said that the U.S. would not be able to make a difference on the ground in Syria for another eight to 12 months because it still needs to adequately train and equip Syrian rebels.

"Our strategy in Syria will demand time, patience and perseverance to deliver results," he said. "Our strategy is to strengthen the moderate opposition to the point where they can, first, defend and control their local capibilities."