The U.S.-Russia agreement on a ceasefire in southwestern Syria, hailed by President Trump as one of the seminal achievements of his bilateral meeting with Russian President Putin in Hamburg, will serve as an early test of Russia’s willingness to work with the Trump administration in Syria. Unfortunately, the agreement leaves open many questions about implementation, and, judging by past practice, is likely to be abused by Russia to help the Assad regime consolidate power. Like the agreement on a collaborative cybersecurity unit, it is just one more indication of how Putin ate Trump’s lunch (or was it dinner?) at the G20 summit.

The ceasefire agreement is formally between Russia, the United States, and Jordan, and applies to a portion of southwestern Syria near the Jordanian and Israeli borders. It reportedly makes geographically delimited “safe zones” off-limits to non-Syrian militias (presumably meaning Hezbollah and Iran’s Quds Force, though it is unclear if these groups are mentioned by name), as well as Al Qaeda and other jihadist groups. The problem with the agreement has to do with enforcement of these “safe zones.” Who determines what groups get to enter or exit, and if violence breaks out, who enforces a return to the ceasefire? Two of the biggest potential spoilers, Iran and Hezbollah, are not parties to the deal. And yet they are Russia’s closest allies in propping up the Assad regime. In concert with Assad, they have waged a murderous campaign against Syria’s opposition for years. The result is a deal that could well leave the proverbial fox – in this case, Russia – guarding the henhouse.

Russian Foreign Minister Lavrov has said that Russia, the United States, and Jordan will be involved in enforcement. However, the Pentagon is focused on operations in Mosul and Raqqa hundreds of miles away; commanders on the ground would surely see a U.S. military presence in southwestern Syria as a costly and unnecessary diversion of manpower in the fight against the Islamic State. Given limited intelligence- surveillance-reconnaissance assets in the region, it is also unlikely that U.S. Central Command would be happy diverting scarce ISR platforms to monitor the ceasefire. And even if U.S. or Jordanian ISR were overhead, would they be able to distinguish Hezbollah or Shia militias who have reflagged themselves as other groups? All this, along with Jordan’s reluctance to go all-in across the border, means that the Trump-Putin ceasefire is likely to hand Russia the keys to southwestern Syria.

Lavrov has also said that Russian military police – a force that has been allied with Assad, Iran, and Hezbollah – would be in charge of determining who has access to the ceasefire zones and what constitutes permissible humanitarian aid. (Recall that in Ukraine, Russia has covertly supplied its proxies with weapons under the guise of “humanitarian aid” to the local population.) The agreement also reportedly gives Russia the right to use force against groups in the ceasefire zone that it deems to be hostile actors, like Al Qaeda. Don’t get me wrong: eliminating Al Qaeda is a fine goal, but the problem here is that Russia has a long track record of referring to every moderate opposition group in Syria as an Al Qaeda offshoot.

Going into the G20 meeting, Putin knew, of course, that Trump would be eager to make progress on Syria. By quickly agreeing to a deal before expert negotiators had a chance to develop a solid monitoring and enforcement mechanism, perhaps involving opposition groups on the ground, Trump appears to have been suckered into a flawed agreement. Without credible monitoring and enforcement, Iranian-backed Shia militias and Hezbollah could start quietly infiltrating southwestern Syria, setting up the Assad regime and its Iranian friends to consolidate control over the border areas near Israel and Lebanon. This would be a major strategic play. Iran’s potential long-term control over the region near the Golan Heights is likely the primary reason that Israeli Prime Minister Benjamin Netanyahu came out so forcefully against the deal, despite having reportedly been consulted on it beforehand.

Trump’s argument that the ceasefire is saving lives, even temporarily, is a powerful one. But even if the death toll slows in the southwestern “safe zones,” regime troops freed up by the agreement are already launching attacks elsewhere, like the new offensive against opposition forces in eastern Ghouta.

The root of the problem here is that Trump seems to think that if only he can talk directly with the Russian leader on what are ostensibly common interests like defeating extremism in Syria, he will succeed where others have failed. But Russia is not really fighting extremism in Syria; it is actually exacerbating it by aligning itself with Assad, Hezbollah, and Iran against a panoply of Sunni groups, some moderate and others extremist. So while Russia has an objective interest in defeating the Islamic State, it also has other proximate aims in the near term: consolidating Assad’s power over the opposition, forcing the international community and the United States to abide by Russia’s terms for the future political makeup of Syria, and building its influence in the region.

The best that can be done now is to quickly remedy the flaws with monitoring and enforcement of the ceasefire by ensuring that opposition groups on the ground have a role, and not just Russian military police.