Oleg Deripaska, last man standing

Who is this man Oleg Deripaska, whose hospitality British politicians from left and right seem so eager to enjoy? Like all the oligarchs who made their first pile amid the turmoil of the imploding Soviet economy in the early 1990s, Deripaska (right) has a history far removed from the floating gin palace moored off Corfu where he entertained both Peter Mandelson and George Osborne this summer.

Now top of the Russian rich list, with a fortune estimated at around £18bn, he is a classic example of the new breed of "entrepreneurs" who snapped up formerly state-owned industries at knockdown prices under Boris Yeltsin's privatisation programme.

With his background as a small-time metals broker, Deripaska, then still in his mid-twenties, decided to carve out an empire

for himself in the lucrative aluminium trade. In the process, he encountered stiff opposition from some equally ambitious rivals: the result was the so-called 'aluminium wars' in which killers from the Russian mafia were recruited to carry out contract hits on industry executives, politicians, journalists and factory managers.

"That was a time when you made sure to look under your car in case a bomb was there," one veteran of the hostilities recalls. In such circumstances, he adds, "there was a temptation to deal with competitors before they dealt with you."

Although the post-Soviet business world was undoubtedly a dangerous place, nothing matched the intensity of the battle for control of the aluminium sector. Deripaska was most closely associated with the struggle to take over