Hello and welcome to NewsHour. It's coming to you live from the BBC World Service Studios in central London.

I'm Tim Franks. And it was by coincidence, it was just a couple of weeks ago that I mentioned on air, on Newsare, for the first time, as far as I can remember, the town of Wan-San on North Korea's east coast.

That was because Kim Jong-un had just inaugurated a brand-new beach resort there.

Today, Wan-San has been back in the news, not for its swimming pools or water slides,

but as the venue for embraces and smiles between Kim and the Russian foreign minister,

Sergei Lavrov.

The North Korean leader promised what he called his full support for Russia's war in Ukraine.

That has been up to now, not just in the vast amount of ammunition Pyongyang is supplying,

but also a considerable number of soldiers to fight on the ground.

Sergei Rachenko is the Wilson E. Schmidt Distinguished Professor at the Kissinger Center for Global Affairs

at Johns Hopkins University and joins us now.

Sergei, thanks for your time here on NewsAir.

What's in it for both sides, do you think?

Well, thank you for having me, Tim. First of all, Russia and Korea now actually are treaty allies.

About a year ago, they concluded a Treaty of Alliance, which obliges each side to come to the other's defense.

And the North Koreans, of course, were involved in Kursk, as you just mentioned,

actually even before the treaty officially came into effect.

And this was Kim Jong-un's initiative.

Now, the question is, why are they doing this?

And I think it's partly transactional.

The Russians are promising them missile technologies

potentially, but also other forms of aid. So it's not entirely altruistic. But generally

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