After the turbulent year that was 2016, it now looks on the surface as if the sky is the limit for the Russo-Turkish double act in Syria. Nothing seems to be able to spoil things for the two countries—not even the shocking assassination of Andrei Karlov, Moscow’s ambassador to Turkey in late December a disgruntled off-duty police officer. When, a month ago, a Russian airstrike killed three Turkish servicemen near the north Syrian town of al-Bab, the two militaries just shrugged it off as an unpleasant incidence of “friendly fire”. The message was loud and clear: what matters most is that Russian and Turkish forces are fighting side-by-side to root out ISIS’ self-proclaimed khalifate. Who could have seen this coming a year ago, when Putin was chastizing Erdogan and the rest of the Turkish leadership as “accomplices of terrorists” for stabbing Russia in the back.

The latest episode of the ongoing diplomatic love-fest between Ankara and Moscow played out when Erdogan visited Putin on March 10. Putin used the opportunity to butter up his counterpart: “We managed to bring the rival forces together and, due to our joint effort, the Syrian ceasefire continues,” he said, praising Erdogan’s “exceptional cooperation” in making sure the December truce holds. The subtext was apparent: Sergey Lavrov and U.S. Secretary of State John Kerry negotiated two such ceasefires over the course of 2016, which both quickly fell apart amidst mutual recriminations.  Turks have turned out to be more reliable than the Americans when it comes to reining in proxies.

But despite the carefully choreographed bromance, a quick look at the actual situation on the ground in Syria suggests that Moscow retains the upper hand in the relationship with Ankara.

While rebuilding Syria as a unitary state is probably no longer possible, the Astana talks seem to have built momentum towards some kind of semi-stable post-conflict arrangement. Unlike with the moribund Geneva process, Iran appears to be on board, having joined Russia and Turkey as the third co-host in Kazakhstan. If things work out, Ankara, Moscow and Tehran could establish a condominium over much of Syria: Assad would consolidate his grasp over the 35% of Syria’s territory he currently controls, with Russia and Iran providing certain security guarantees to their proxy’s statelet. Turkey, in turn, would carve out a zone of influence south of the 900-km long border it shares with Syria.

And it’s more complicated than that. The above-sketched tripartite arrangement doesn’t even begin to take the United States and its Kurdish allies into account.

Turkey had hoped to play a facilitating role for any emergent partnership between Washington and Moscow, but Syria has complicated that calculus. A meeting last week in Antalya, between General Hulusi Akar of Turkey, Joint Chiefs Chairman General Joseph Dunford, and General Valery Gerasimov, chief of the Russian General Staff, is illustrative of the conundrum Ankara finds itself in. The talks were the result of a standoff around the northern Syrian town of Manbij, east of the Euphrates river, where both Russia and the United States have sent patrols in order to keep Turkish and Kurdish forces from fighting each other. Instead of mediating between Washington and Moscow, Turkey and its allies in the Free Syrian Army were one of the proximate causes for the standoff.

And this is where bad news start for Erdogan. Turkey has already given much ground to the Russians. It has backtracked from its supposedly non-negotiable demand that Assad should step down, and Astana marks another step in the direction of fully accepting that reality. Indeed, the Turks are in all likelihood already backchanneling with Damascus, having ostensibly burned all bridges to the regime in August 2011. What Turkey hopes to obtain in exchange for being flexible on Assad is gaining a free hand in northern Syria against the Kurdish Democratic Union Party (PYD), an offshoot of the outlawed Kurdistan Workers’ Party (PKK) and its militia, the People’s Protection Units (YPG).

But if Erdogan assumes that either Russia or the U.S. will easily give up the Kurds, who have proven of immense value on the ground as a force capable of containing and rolling back ISIS, he is mistaken. The standoff around Manbij is but one example. Indeed, after the first round of talks in Astana, the Russians circulated a draft Syrian constitution which foresaw a high degree of decentralization and hinted at some degree of autonomy for the Kurdish community. PYD members even attended a meeting at the Russian Ministry of Foreign Affairs to discuss the document, together with representatives of the Syrian opposition. And this is not the first time that Russia has floated such ideas, ideas, it’s important to note, that are vehemently opposed by both Turkey and the authorities in Damascus. There are rumors that during their rapprochement, Putin promised Erdogan that he would never back the formation of a fully autonomous Kurdish state in the Syrian territories. From Putin’s perspective, however, the decentralization of the Syrian state—pretty much an inevitability given the facts on the ground—gives him lots of room to maneuver. And he is clearly taking it.

Similarly, the United States is unlikely to sever ties with the YPG-dominated Syrian Democratic Forces (SDF), the umbrella militia involving Kurdish, Arab and other fighters it helped create in 2015. Despite Turkish objections, the SDF will be a key part of the looming anti-ISIS operation against Raqqa.

It is difficult to foresee the trend towards de facto Kurdish autonomy being dealt a major setback at this point. Only a massive military push could conceivably begin to turn back the clock, and an all-out invasion by the Turks, over the objections of both the Russians and the Americans, is highly unlikely to say the least. Given what we have seen thus far of Euphrates Shield, Turkey is sticking to modest goals and is unwilling to overextend its military.

Given all these complications, chances are that it is Turkey dancing to the Russians’ tune than the other way around.  There are several other factors at play that strengthen Putin’s hand.  Firstly, not all economic sanctions imposed in response to the downing of Russia’s Su-24M aircraft have been lifted.  That leaves Moscow with some extra leverage it could bring to bear on the Turks. Second, and more important, Erdogan is coming closer to a major test to his power at home—a referendum over the changes of the constitution to install a presidential republic abolishing the current parliamentary model. It is there that his priorities lie, rather than in Syria.

The Russo-Turkish double act may soon start showing its limits. Putin and Erdogan will studiously keep the appearance that they are edging closer to a deal on Syria. In reality, their newly rekindled camaraderie will continue being little more than a façade which just about hides the serious differences that remain in place between Russia and Turkey.