Yesterday’s agreement for a cessation of hostilities in the Syrian conflict – including provision for humanitarian aid deliveries – is welcome news from an increasingly bloody conflict. The deal has been greeted with justifiable skepticism from observers around the world, who note the many and varied problems inherent in the proposed agreement. This is not a formal ceasefire, and it faces long odds of successful implementation. But that doesn’t mean it isn’t worth supporting to the fullest extent possible. If it does succeed in reducing violence inside Syria, it just might act as the necessary first step to a more comprehensive ceasefire and transition agreement.

One could hardly have imagined a more ill-omened location for the agreement, which was announced yesterday on the sidelines of the Munich Security Conference. The agreement itself calls for a cessation of hostilities inside Syria – though it does not apply to either of Syria’s main extremist groups, ISIS or Jabhat al-Nusra – and for the rapid provision of access for the delivery of humanitarian supplies to Syria’s besieged cities. It is not an immediate deal: parties have one week before it takes effect. Yet if the deal sticks, it will help to stem the flow of Syrian refugees and provide desperately needed humanitarian assistance.

There are certainly reasons to doubt the deal’s feasibility. It is accurately described as a cessation of hostilities, rather than a ceasefire, which would require monitoring and enforcement mechanisms. This deal lacks either; without a relatively neutral third party monitor, it will be difficult to ascertain from dueling propaganda whether it is actually working. Nor are the main belligerents – the Assad regime and the Syrian rebels – actually parties to the agreement, another reason for its less formal structure. The deal will rely heavily on the ability of Russia and the U.S. to pressure conflicting parties.

The biggest obstacle to any peace remains the same: the definition of “terrorist.” This agreement doesn’t apply to extremist groups, meaning that US airstrikes against ISIS will continue unabated. But it is also unknown whether Russia will reorient its own airstrikes, which have often struck at more moderate anti-Assad rebels that the Russians describe as terrorists. The problem is compounded by the fact that Jabhat al-Nusra itself doesn’t hold geographically distinct territory, with members spread throughout the West of Syria who mingle and cooperate with other rebel groups. It will be exceedingly hard to tell whether Russian airstrikes are aimed at Nusra alone, or at other groups.   

It is also true that the one week delay before hostilities end will likely allow Russia and the Assad regime to solidify the gains they’ve made in and around Aleppo, freezing the conflict in a strategically advantageous way. Russia pulled a similar stunt during the Ukraine conflict, delaying the implementation of a ceasefire in order to solidify rebel control over the key town of Debaltseve. Yet if Russia continues its indiscriminate air campaign past the one week mark, however, it will suffer a reputational and public relations costs. 

For all these flaws, the deal agreed in Munich offers a potential way forward for a peace process which has stalled, in a situation where there are few other good options. The alternatives are far worse: an impossible to protect no-fly zone which would could bring the US and Russia into direct conflict, a military intervention by Turkey or Saudi Arabia aimed at backing favored rebels and toppling Assad, or simply the incessant grinding humanitarian tragedy of the ongoing war.

And if the cessation of hostilities is successful, it will provide much needed space for humanitarian aid to flow into besieged areas like Deir ez-Zor and Aleppo, as well as providing the time and minimal level of trust needed to reopen the stalled Geneva peace process. There were also hints from Kerry and Lavrov that we might see increased U.S.-Russian military cooperation against ISIS, which has so far been inhibited by Russia’s wholehearted military support for Assad. Secretary of Defense Ashton Carter spoke this week in Europe about the need to accelerate the campaign against ISIS. But this is likely to be impossible in the absence of a peace process in Syria and increased coordination or cooperation with Russia.

There are many good reasons to be skeptical about yesterday’s announcement. As Secretary Kerry noted, “the proof of commitment will come only with implementation.” Despite that, it offers the potential for a path forward in a conflict that has become increasingly intractable and bloody. It might fail. But until it does, the United States should do everything in our power to help it succeed.