President Barack Obama is asking Congress for an extra $165 million to boost the Syrian opposition as part of his $5.6 billion request to fight the Islamic State (IS), a tacit acknowledgment that the group can’t be defeated in Iraq alone.

The request is included in a 34-page letter from the Office of Management and Budget that was sent to House Speaker John Boehner, R-Ohio, on Nov. 10. Congress returns from its election day recess on Nov. 12 and administration officials are urging a quick vote so they can start deploying an extra 1,500 troops to help the Iraqi army battle IS.

The request includes $100 million in Economic Support Fund spending to support “Syrian stabilization strategies” and allow the State Department to “expand its engagement with the moderate Syrian opposition” and “help develop the capacity, cohesion, and credibility of the opposition.” It would also increase the Peacekeeping Operations budget by $65 million for “programs to bolster the capacity of the moderate Syrian opposition to counter [IS] and other extremist groups.”

“The Department of State will expand its engagement with the moderate Syrian opposition,” the OMB letter states, “to help develop their capacity to provide local security in areas previously under IS control and foster the conditions that lead to a political settlement.”