A plane arrived in Ankara in the afternoon and disgorged the collective elite of Russia’s political prisoners, as the biggest swap since 1985 was completed in a landmark deal.

Rumours that began yesterday rapidly gelled into a newsmaker after some 16 people were released from Russian jails, pardoned and sent on their way as eight Russian prisoners, mostly cybercrooks, a couple of spies and one assassin, were exchanged.

Nothing has been officially confirmed yet. The Kremlin has yet to comment and the US has confirmed the exchange, but only in comments by an unnamed official. It is possible that the Russian prisoners are still in transit, hence the secrecy.

But the deal is significant. The first thing to note is the lopsided nature of the exchange. In the world of diplomacy, expulsions and prisoner swaps are usually done on the basis of equality: like-for-like.

Amongst those reportedly freed is Paul Whelan, a former US marine who has been in jail on an espionage charge since 2018. The only reason he was not included in the December 2022 one-for-one swap of US basketball player Brittney Griner, who was traded for notorious Russian arms dealer Viktor Bout, was the Kremlin said that Whelan was an agent and so required an exchange of comparable value. The Kremlin wanted to get assassin Vadim Krasikov back and it is widely believed they arrested Gershkovich to get a tradeable card. Gershkovich was convicted for spying, marking his card with the same value as Krasikov.

Whelan’s family will be very relieved to have him back, but stepping back and one of the odd things about this deal is that Russia released twice as many prisoners than the West did. And moreover, those they released include some of the country’s highest value opposition leaders such as Kara-Murza and Ilya Yashin, who were two of Russia’s most prominent opposition leaders. Oleg Orlov was also the chairman of Memorial, Russia's biggest NGO and also a Nobel prize winner to boot. Amongst those being sent back to Russia is Vladislav Klyushin, who is the developer of a media monitoring system for the Kremlin. That is not an equitable trade. The only really important prisoner amongst those released from the US was the Berlin assassin Krasikov.

Why would Russian President Vladimir Putin agree to a deal like this? The answer is probably because the Kremlin considers Krasikov to be nash (Russian: ours), not just in the sense he is a Russian citizen, but more specifically because he is FSB. Putin needs to show that he will take care of the siloviki, the security services faction, as they are the bedrock of his grip on power. So leaving Krasikov in a German jail after he got caught carrying out Kremlin orders was not an option for Putin. (Two other famous spies, Artem and Anna Dulcev, were also released from a Slovenian jail as part of the swap.)

Another interesting aspect of the timing of the deal is that it comes in the midst of Putin’s increasingly clear signals that he wants to end the war in Ukraine and ahead of possible November talks. He has said repeatedly in recent months that he is willing to negotiate and has offered to pick things up from the Istanbul peace deal struck in April 2022.

The prisoner swap can be taken as another signal that Putin is in the mood for compromises ahead of the second peace summit in November.

Of course, the two sides are still very far apart, but Ukrainian President Volodymyr Zelenskiy is also moving towards the middle ground. He said this week that he may call a referendum on the issue of giving up land in any potential talks, which is to say he is now conceding the need to at least talk about territorial concessions – a big step back from his previous maximalist position that Russia had to withdraw all its forces from Ukraine entirely, including the Crimea, before he would even start negotiations.

The need for a referendum is widely seen as a prerequisite for any meaningful talks and has only become a thing in the last month or so. Now Zelenskiy has said the word too.

The mood in Ukraine is darkening steadily and will darken further as a winter without power closes in. The first F-16s arrived in Ukraine yesterday, but they only have six pilots and go up against 350 Russian state-of-the-art fighters so they can’t actually be used in combat. Zelenskiy has politely said that the new planes are not a “strategic” addition to his forces.

The prisoner swap will also be a big feather in the cap of US President Joe Biden ahead of the November presidential elections, but the US also clearly wants the war to end. The $61bn aid package approved on April 20 is expected to be the last big package from the US and both sides are now actively looking for a palatable exit from the conflict.

The prisoner swap deal could be a Russian olive branch and designed to signal that Putin will be willing to make compromises. Zelenskiy's talk of a referendum could be the same, or at least an admission that the outlook for Ukraine’s victory is bleak. Zelenskiy's push to organise a second peace summit in November to which both China and Russia will be invited is more of the same.