In the judgement this afternoon, Sir Robert Owen also agreed not to include any evidence questioning whether the UK authorities could have prevented Litvinenko's death.
The coroner admitted the exclusion of this evidence could result in the inquest becoming "incomplete, misleading and unfair" and took the unusual step of inviting the government to hear the secret evidence in a separate secret inquiry behind closed doors.
The inquest is scheduled to begin on 2nd October.
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