Syrian opposition leader Ahmad Jarba said Wednesday that rebels would soon receive advanced weapons because they have been waging a two-front war against regime troops and militant extremists from the Islamic State of Iraq and Greater Syria (ISIS).

In Washington, Kerry admitted that Assad was making gains on the ground, but he denied U.S. policy in Syria was failing.

Kerry pledged the administration would work with Congress as well as internally to try to figure out how to push the Russians to use their influence on Assad to help improve conditions on the ground.

A State Department official, meanwhile, told American lawmakers that the Iraqi government needed to do more to prevent Iran from flying weapons and fighters through its airspace en route to Syria.

Iraqi Prime Minister Nouri al-Maliki has been accused by Washington of allowing Iran to fly planes through Iraqi airspace and send support to Assad’s regime.

Zawahiri says Nusra Front is Al-Qaeda’s official branch in Syria and has distanced his organization from ISIS, unsuccessfully ordering them to return to Iraq.