A former spy and his daughter, who were poisoned by the deadly nerve agent Novichok, will not give evidence at the Russian-state Salisbury poisonings inquiry over fears for their safety.

The judge leading the inquiry said if Sergei Skripal and his daughter Yulia are identified and their current whereabouts are discovered, the risk of an attack on them “is not properly controllable”.

Dawn Sturgess, 44, died after being exposed to the chemical weapon which was left in a discarded perfume bottle in Amesbury, Wiltshire, in July 2018.

It followed the attempted murder of Mr Skripal, his daughter and ex-police officer Nick Bailey, who were poisoned in nearby Salisbury in March that year.

All three survived, as did Ms Sturgess’s boyfriend Charlie Rowley.

In June, a preliminary hearing for the Dawn Sturgess Inquiry at the Royal Courts of Justice heard that the Sturgess family wanted the Skripals to give oral evidence to address “unanswered questions”.

However, Lord Hughes of Ombersley, in his ruling this month, said there is an “overwhelming risk” of a physical attack on the Skripals.

He went on: “There is every reason to be satisfied that an attack similar to that which appears to have taken place in 2018 remains a real risk, either atthe hands of persons with the same interest as the 2018 attackers, or via others interested in supporting the same supposed aim, if either Sergei or Yulia can be identified and their current whereabouts discovered.”

The judge said it would not be possible to maintain proper security if they appeared in person, also saying that they must not give evidence remotely as their location could be worked out.

He wrote that the Skripals have provided further statements addressing specific questions raised by the Sturgess family and that transcripts of police interviews with the father and daughter had been disclosed.

Lord Hughes of Ombersley went on: “I am quite satisfied that the risk to both Skripals of physical attack clearly outweighs the advantage to the inquiry of their giving oral evidence.

“The disruption and intrusion into their private lives, whilst alone not sufficient to dictate the conclusion that they should not give evidence, adds to the balance a further reason why they should not.”

The judge also ordered that video and audio of the Skripals being interviewed by police in 2018 must not be played for the same reasons.

He wrote: “To play recordings of the 2018 interviews with either or both of the Skripals would afford an unparalleled opportunity to any interested person to see and to hear them in person.

“That would undoubtedly enormously add to the risk that someone will identify them.”

The public inquiry hearing is due to begin at The Guildhall in Salisbury on October 14.