Chairman Robert Owen’s report will be published on Thursday, just under a year after the probe opened.
The inquiry was tasked with identifying where responsibility for Litvinenko’s death lies. The report is expected to set out “appropriate recommendations” in his report, but Owen cannot make any findings of civil or criminal liability, nor award any compensation.
Litvinenko, a former KGB agent, died in November 2006 aged 43 after drinking tea laced with radioactive polonium in a London hotel.
Police concluded that the fatal dose was probably consumed during a meeting with Dmitri Kovtun and Andrei Lugovoi at a hotel in central London.
In the years that followed, the case attracted an avalanche of claims and theories and threatened to plunge Anglo-Russian relations into crisis. Last year, the events were examined in forensic detail by the inquiry, convened following a long legal battle by Litvinenko’s widow Marina.
During six months of hearings, dozens of witnesses gave evidence and a huge number of documents were examined.
The killing was described as a “nuclear attack” on the streets of London, and some of the testimony at the inquiry was highly technical. A Home Office pathologist described the post- mortem examination of the poisoned spy as”one of the most dangerous ever undertaken in the western world”, while the inquiry heard about a trail of radioactive traces found in locations around London.
Much focus will fall this week on the report’s conclusions regarding allegations that the Russian state was behind the murder.
On his death bed, Litvinenko pointed the finger at Russian president Vladimir Putin. The Kremlin has always denied the claims.
In his closing speech, Ben Emmerson queen’s counsel, representing Litvinenko’s widow and son Anatoly, said: “When all of this evidence is viewed in the round as it must be, it establishes Russian state responsibility for Mr Litvinenko’s murder beyond reasonable doubt, and if the Russian state is responsible, Vladimir Putin is responsible.”
The world of espionage also featured heavily during the hearings.