The Russian invasion of London and the Home Counties hasn’t had much impact on daily life in the capital, unless you’re a consigliere-type lawyer, or run a concierge company that panders to oligarch whims. After all, we’ve been drinking vodka here for centuries, and caviar (or as anglicised White Russian aristocrats used to call it, ‘fish jam’) has been a delicacy since the Revolution.

But that could all change with the banya-fication of the capital. A banya is a Russian alternative to a Turkish bath, though where the Turks favour marble and massages, the Russians are keener on raw wood and beatings with birch twigs - it’s all generally hotter and more intense. This was an experience Lord Mandelson once found highly invigorating in the presence of aluminium tycoon Oleg Deripaska and Lord Rothschild’s financier son, Nathaniel. Rothschild described the experience thus: “We were beaten by a 25-year-old banya keeper man, who has spent his life perfecting the art of banya. Then we jumped into ice-cold water. It is the best way in the world to beat jet lag and everything else. It was incredibly enjoyable.”

Now we all have the chance to enjoy the same invigorating experience, if not necessarily in the presence of a clutch of billionaires. Though don’t underestimate the appeal of the banya to the powerful and secretive. President Putin is said by Newsweek to swear by his regular immersions in boiling hot air and freezing cold water. And in one episode of the police comedy Brooklyn 99 (I know, you’ll have to forgive me, but lockdown was long), our hero Jake Peralta goes undercover in a bathhouse to talk secrets with a counterfeit clothes manufacturer. The crook only does business in the steam room in the nude for fear of weapons and hidden mics.

There is definitely something about the combination of trepidation and relaxation that a really good banya delivers, along with refreshingly unhealthy, calorific and alcoholic refreshment - no carrot juices here - that invites confidences. Then factor in that you’re often completely naked barring a thick felt hat that looks like a campanulate mushroom, and dignity and discretion are left behind along with your clothes in the locker room. One colleague overheard an incredibly revealing exchange between two Russians in a bath house in the height of lockdown.

They were discussing, ruefully but not regretfully, the fact that they’d had to pay £10,000 fines for breaking Covid quarantine, and how they were going to spend their summer island hopping from Capri to Ibiza one step ahead of the pings.

According Robert Procopé, the owner of The Bath House, a new banya round the back of Buckingham Palace, the end of the Soviet Union happened when politburo leaders gathered in a baths to plan the removal of Mikhail Gorbachev but failed to arrest Boris Yeltsin at the same time. So Yeltsin stepped in to the power vacuum. Of course, he celebrated his victory in a banya.

As for the health benefits, apparently Peter the Great said his army had no need of doctors: ‘the banya alone is enough.’ Hot and cold therapies strengthen the cardiovascular system, open your pores, flex your muscles, stimulate the immune system and help you shed weight…. What can’t they do?

My banya correspondent, Veronika Matvejevskaja, whose father actually built his own bath house (he’s very practical) says it’s one of the few things she really misses about her home in Russian-speaking Estonia. ‘Hot humid steam helps to relax muscles and purifies skin better than any £80 facial,’ she says. ‘The next day I feel like a newborn. The secret is to go to bed with a cup of fresh herb tea and a spoonful of honey straight after your bath.’

In The Bath House, as in all self-respecting banyas, you are looked after by extremely expert and single-minded staff. ‘There is great skill to being a banshchik (banya specialist),’ says Procopé, a former City financier. His staff are mainly from the Baltic states and as Procopé knows, ‘a good banshchik is highly prized and people will return to the same person. It’s a bit like going to the same hairdresser for years.’ He also hosts bath attendants from Sanduny, Moscow’s most famous baths, who jet in like visiting professors.

I have a Muscovite friend who swears by the Sanduny as ‘the perfect place to get clean and disclose, or find out, secrets.’ She also reveals dark doings in among the birch twigs: for super-rich banya aficionados, it’s not the quality of the fittings that counts, but the pedigree of your banshchik. ‘It’s all about people nicking really good banshchik from each other,’ she says. ‘And there’s even a World Cup to work out who’s the best.’

The process is that you arrive in the baths, strip to your skin (or swimsuit if you’re feeling coy), wrap yourself in a large white sheet and go and sit in the cafe where you warm up for the ordeal ahead with something authentically Russian like pelmeni (dumplings) or borscht, or cut to the chase with blini and caviar washed down with tea, kvas (a fizzy drink made from rye bread), beer (Procopé serves Rothaus German beer), or Beluga vodka.

After about half an hour, you hop into the sauna, naked but for your felt hat, that protects your hair from melting in the 100C heat. English wusses can normally only cope with this for ten minutes, max, but a really determined Russian can stay in the sauna apparently indefinitely. Then you stand under a bucket of icy water, pull a chain, and empty the whole thing over your head. Or, if you prefer, you can plunge into a cold bath (it can be as chilly as 4C). Either which way, you’re boiling, then you’re freezing. And you repeat this process until the banya’s presiding expert tells you it’s time for your pareniye.

This is the Mandelson-birch-twig bit. I was there with a friend (it’s single sex only with men and women on alternate nights, unless you have a private banya) and we were laid down on wooden beds in a wood-lined room with an open stove pumping out heat while two muscular young men in swimming shorts covered our faces with bunches of cold birch twigs and then alternately beat - lightly, they don’t leave a mark - and stroked us with hot bunches of twigs.

Neither of us could last the full half hour in the pareniye, and our disappointed banchiks said we’d have to come back to build up our resistance to the wet heat. But it was a very intense 25 minutes. And then they sluiced us down with freezing water and delivered us back to the cafe very much more relaxed than we went in. Procopé says, ‘I hesitate to use the word transformation, but the whole process can shift your mood and help to reset you. It can be a bit like therapy – you feel “held”.’ Certainly if I needed to mend a relationship, or get something off my chest, there’d be no better way of warming up.

The last bit of my experience was the least exotic but in some ways the most remarkable. It was a straightforward massage by a young Eastern European woman that was just half an hour long and completely free of silly whale music and incense. But she seemed to home in on exact sore spots on my back that I hadn’t even been aware of, and drilled into them with agonising expertise. She also manipulated my neck so it stretched an extra inch and a half in all directions. She also told me I had - at some point in my childhood - broken my coccyx which is something I had never even noticed. She was a revelation and I’m afraid I’m not going to tell you her name in case you try to lure her away from the Bath House.

You can spend hours - days - in a banya. On one trip to Moscow, friends and I went to a banya in which half the clientele were supermodels gearing up for a night on the tiles, and the other half were babushkas winding down after a tough week. It was both intensely glamorous and extremely cosseting. I hadn’t thought you could replicate that experience a stone’s throw from Hyde Park Corner. How wrong I was.

There’s no need to hop on a plane to go somewhere rich and strange. You just need to book into the Bath House.

For details visit www.russianbanya.co.uk

The best bathhouses in London

South Kensington Club

The two private banya cabins available for members include a private balcony, plunge pool, treatment room and a dedicated Banschik therapist.

From £300 for a private Banya cabin, www.southkensingtonclub.com

Aire Ancient Baths

Ancient thermal baths are available at varying temperatures at this central London spa. You’ll have access to the relaxation area to rest on warm marble stones afterwards.

The Ancient Thermal Bath, £90 for 90 minutes, beaire.com

Banya No. 1, Hoxton

The coveted spot in Shoreditch is London's first Russian bathing club and is known to have a number of celebrity regulars. Visitors can choose from men-only, women-only and mixed days or a private spa experience.

3 hour session, from £62, gobanya.co.uk

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