Will the UK warm to Finland's naked, sauna diplomacy?

Finnish diplomats have used saunas as a relaxed venue for discussing international policies and solving problems for years. Now there is one in the UK. But what's the appeal? The BBC's James Landale joined the new sauna society inside Finland's embassy in London to find out how it works.

Diplomacy can come in many forms; international summits, high level negotiations, and smart receptions where people sip champagne and eat fancy chocolates. But diplomats from Finland have what they say is a secret weapon, a unique way of engaging with people - just so long as they are ready to take their clothes off.

For years, there has been a diplomatic sauna society in Finnish embassy in Washington DC, as well as others around the world. And now there is also one in the basement of the embassy in London, after it opened last year.

The format for "sauna diplomacy" is simple. Finnish diplomats invite their contacts to the UK embassy. Introductions are made, a drink is had, and then it's time to gets changed. The women head off to the sauna by themselves. When they are done, the men have their turn. At the end, everyone gathers for another drink and a small bite to eat.

Call it naked networking. And apparently it works.

"Sauna is an old Finnish tradition, an integral part of Finnish way of life," says Heli Suominen, press counsellor at UK's Finnish embassy. Sauna diplomacy, she says, is all about building trust and forging friendships.

"It creates a good ambience for having frank discussions. The fact that you're not fully dressed helps because everyone is equal, it's easier to forget your roles and titles. So you can actually go to the bottom of things." Which is one way of putting it.

The idea is that getting hot and sweaty relaxes all sides, builds trust and reduces tensions, making it easier to build relationships. And that is exactly how it was when I took part in an evening of sauna diplomacy in London.

There are clear rules. You shower first, you wear swimwear or a towel, and men sweat with men, women with women. As you enter, you get what is called a "bum towel" to sit on for protection against the heat. The thermometer in my sauna said the temperature was about 80C. And so you then sweat and chat. Very quickly barriers are broken down.

Sauna diplomacy does not work in all countries - some cultures are less accustomed to near-nudity in public - and there is something very intimate about being squeezed into a small, dimly lit space with five other men. But when I asked if anyone felt uncomfortable, no-one said yes.

Federico Bianchi, a diplomat currently working for the European Union in London, says he enjoyed it because it was so different - engaging in diplomacy without the usual tools of his trade: a sharp suit and a mobile phone.

"It is quite peculiar not to be clothed and not to be able to rely also on your look and the perception that you think your counterpart can have of you," Bianchi offers. "You just have to rely on the naked words, and what you say."

There have been times when Finnish leaders used the sauna for more direct diplomacy. In the 1960s, Finland's Cold War leader - Urho Kekkonen - took the then President of the Soviet Union Nikita Khrushchev into an all-night sauna and persuaded him to allow Finland to integrate with the West. In 2005, when Vladimir Putin visited Helsinki, he had a sauna with the husband of the Finnish president, Tarja Halonen, and described it as "a wonderful experience".

But these days sauna diplomacy is more about cultural engagement. Sanna Kangasharju, a Finnish diplomat currently working for the European Parliament, used to run the sauna society in Washington DC.

"It was hugely popular," she says. "It became a kind of underground thing and everybody wanted to have the ticket to the sauna society. Every country has an embassy in Washington - we were all fighting for the attention of the reporters, [and] people working in Congress. And once you created something where it was a little bit difficult to get - we could invite only 25 people once a month on a Friday evening - you wanted to have that ticket."

Sanna feels she would not have developed such a strong network in the US capital without the sauna. "They want a special experience," she says. "When you go to a reception and you meet other people, you can say: 'Oh, I didn't recognise you with your clothes on'. You want to be a part of that club."

The elephant in the sauna for many will, of course, be sex. In some cultures, the two are linked. But not, says Heli, in Finland.

"Finnish sauna is very decidedly a non-sexual space, even more than other places where you meet people," she explains. "It's almost sacred to us that it's a safe space for everyone. The point of sauna is that everyone feels comfortable and respected."

Some diplomacy can involve eating and drinking too much. It can also involve long hours of work. But after an evening of sauna diplomacy we felt good, the strains of the day sweated into the night.

We left with a certificate declaring our membership of the Diplomatic Sauna Society. Its motto: "All people are created equal, but nowhere more so than in a sauna."