(Chip Somodevilla/Getty)

Barack Obama and Vladimir Putin's relationship has always been, shall we say, fraught, but on Monday they shared a toast at the United Nations that looks to have been, even by their high standards, pretty weird.

There's so much to take in here. The nuclear powers side-eye. Putin's almost triumphalist smirk; Obama's undisguised loathing (there's an unmistakable "let's get this over with" look on his face) of the man with whom he's touching glasses. The discrepancy in size between the two men — look at how much farther Obama's arm reached than Putin's — adds another layer to it all. But their eyes sure are locked.

I thought Mashable's global news editor, Louise Roug, put it best when she wrote, "They clearly see side-eye to side-eye on things."

This was a scripted event, but there was still plenty of reason for awkwardness. President Obama's speech to the United Nations General Assembly that morning opened with an extended subtweet of Russian President Vladimir Putin, lamenting for example that "some major powers assert themselves in ways that contravene international law" (gee, I wonder which major powers). From there, Obama transitioned from implicit criticism of Putin to explicit, going point by point on Russia's misdeeds in Ukraine.

Putin returned the favor, giving a lengthy UN address of his own on Monday — his first since 2005 — blaming the United States for the wars in Libya, Syria, and Ukraine.

But both Obama and Putin, in their respective speeches, paused briefly in trashing one another to suggest, however tentatively, that they could also maybe work together to resolve Syria's civil war.

And that leads us to that afternoon's bizarre toast. What you're seeing there is the mutual offer to work together in Syria — "ugh, fine, maybe if we really have no other choice" — colored by a deep mutual enmity that included, in just the hours before their meal together, some pretty fierce trash-talking on the world stage. Truly, this is side-eye diplomacy at its height.

You can also see a bit of their personalities coming through: Obama, never particularly talented at hiding his disdain for his adversaries and not even really trying here; Putin, ever delighted in his ability to troll the Americans, smiling at having forced himself back to the grownups' table. And that, in some ways, is what this is all about: Putin got Russia kicked out of the league of respected major powers over his invasion of Ukraine (Obama referred to Russia as a "regional power," which, sick burn), and kicked out of the G8. Now, he may believe, he's won his way back by intervening in Syria.