Lakshmi Mittal is spending Christmas at his Alpine holiday home in St Moritz to indulge his latest pastime: cross-country skiing. The 56-year-old businessman believes the downhill version of the sport is for “lazy people” and prefers to push himself up hills instead.

Those who know the Indian steel entrepreneur would expect nothing less. Over the past three decades he has assembled, from the ground up, by far the world’s biggest steel business with three times the output of its closest rival. He has become the world’s fifth richest person, with a fortune estimated at $23.5bn by Forbes magazine.