A post-mortem carried out on the body of Russian oligarch and Kremlin critic Boris Berezovsky on Monday found the cause of death to be "consistent with hanging", British police said.
The 67-year-old exile was found dead at his mansion in Ascot, west of London, on Saturday.
"The results of the post-mortem examination, carried out by a Home Office pathologist, have found the cause of death is consistent with hanging," said a Thames Valley Police statement.
"The pathologist has found nothing to indicate a violent struggle," it added.
Other tests including a toxicology examination were being carried out, but results will not be known for several weeks, police said.
A forensic examination of the property "will continue for several days".
"A cordon will remain in place until this work has been completed, to protect the scene," the statement added.
Police have already said there is no indication that anyone else was involved in the death.
"I would like to reiterate that we have no evidence of any third-party involvement at this stage," said Detective Chief Inspector Kevin Brown of the local Thames Valley Police force.
Because of the sensitivity of the case, it was a pathologist from the interior ministry who undertook the examination instead of a local expert, the force said.
Berezovsky, who had survived at least one attempt to kill him, was found dead on the floor of the bathroom at his luxurious home in Ascot, an upmarket town in Berkshire.
A member of his staff, believed to be a bodyguard, broke down the bathroom door after he had not heard from the tycoon for several hours.
A paramedic went to the house but Berezovsky was dead when the medical worker arrived.
Officers trained in detecting chemical, biological, radiological and nuclear material inspected the property after a device carried by the paramedic suggested the presence of a possibly hazardous substance, but they gave it the all-clear.
Police said Berezovsky's family had asked that some details of his death not be released until after the post-mortem in order to give them time to speak to his children first.
Friends have said Berezovsky had been depressed in recent months after losing a multi-million-pound court battle with Roman Abramovich, another British-based Russian oligarch who owns English Premier League football club Chelsea.
Berezovsky had sought more than £3 billion ($4.75 billion, 3.8 billion euros) in damages, accusing Abramovich of blackmail, breach of trust and breach of contract in an oil deal.
But the judge in the case described Berezovsky as "an unimpressive, and inherently unreliable, witness".
Forbes magazine published an interview on its website that Berezovsky gave to journalist Ilya Zhegulev on Friday in which he said his "life no longer makes sense" and that all he wanted to do was return to Russia.
But given that Berezovsky's friend and fellow Kremlin critic Alexander Litvinenko was killed by radioactive poisoning in London in 2006 -- an assassination that Litvinenko's widow maintains was ordered by Moscow -- police will continue to investigate.