Boris Yeltsin cheerfully flagellated visiting heads of state during bouts of “banya diplomacy”. Vladimir Putin soaked up the steam on the day that Russians elected him President.

The banya, or steam bath, has been a feature of life in Russia for centuries, a purifying rite that is partly to do with the Russian soul, and partly an excuse to socialise over food, vodka and birch-leaf lashings.

Now enthusiasts in the Siberian city of Barnaul have developed the ultimate banya: a mobile steam cooker that lets people sweat to their heart's content wherever they like. They have converted a Gaz-66 military lorry into a wood-lined sauna, with a steam room and resting area.

Oleg Kochetkov, owner of the bathhouse on wheels, said that customers could rent it for 1,200 roubles (£26) an hour or arrange a day trip into the countryside — with driver and banya “technician” — for £100. The idea was developed by Igor Chupin, who worked for months to build the sauna, complete with a 100-gallon (450-litre) tank on the roof to provide the steam, and now acts as driver and cook.

Mr Kochetkov said that the service was booked most weekends. “It's most popular with middle-class business people but we also have orders from families. If people want us to drive it outside their apartment building so that they can enjoy a banya for an hour, we are happy to.”

The banya-on-wheels cost about £10,000 to build, seats five people comfortably and is heated by a traditional wood-fired stove. It has a television, DVD player, generator and a fridge to keep the essential supplies of beer and vodka cold.

“It's all very Siberian — you can watch TV, listen to the radio, drink beer and sing songs,” Mr Kochetkov said. “My friends and I like to rest in the countryside and we thought it would be fun to take a banya with us. If you go to a hotel or a seaside resort then you can always find one, but it's not so easy if you just want to drive into the woods or by a lake.”

Russians are devoted to the banya's elaborate ritual of steam-filled rooms, cold showers and intermittent but vigorous beatings with clumps of birch leaves, said to improve the circulation. Many swear by its medicinal effects in maintaining a healthy mind and body during the brutally cold winter.

Deals are often brokered at a banya. Mr Yeltsin's memoirs record the banya's critical role in 1989 when a group of people urged him to continue his fight against the Soviet leadership. He wrote: “That moment in the banya was when I changed my world view, when I realised I was a communist by Soviet tradition, by inertia, by education, but not by conviction.”

Mr Putin has been a less ardent fan in public, but he showed his common touch by announcing that he would spend the day at a country banya after he had voted for himself in the 2000 presidential election.