Thames Valley Police released a statement saying there were no signs of a struggle, The Guardian reported. Berezovsky's body was discovered Saturday by his bodyguard in a locked bathroom in a mansion in Ascot legally owned by his ex-wife.
"The results of the postmortem examination, carried out by a Home Office pathologist, have found the cause of death is consistent with hanging," police said.
Berezovsky, 67, a civil engineer with a doctorate in applied mathematics, became a billionaire when state-owned companies were privatized. He became a critic of Vladimir Putin, and Britain granted him political asylum in 2003
His former business partner, Roman Abramovich, won a lawsuit against Berezovsky, leaving him with large legal bills and frozen assets. In an interview Friday, Berezovsky reportedly told a Russian journalist he had "lost the meaning of life."
Sasha Nerovina, a friend of Berezovsky's ex-wife, Galina, said his family, which includes six children by three women, hope the investigation into his death will end quickly.
"For the children it is the most tragic time. They are extremely shocked and devastated," she told The Guardian. "If you look at Russian TV, some are saying he was killed, some are saying he may have staged his own death to appear as if it came from Putin's hand. There are a lot of conspiracy theories and when you lose someone you love, you don't want them to interfere with your grief."
Friends said Berezovsky had been treated for depression, apparently successfully.
Celebrity Couples of 2014 [PHOTOS]