Theresa May has said “justice is unlikely” for the victims of the Novichok nerve agent attacks, days before an independent inquiry begins into the Russian-state Salisbury poisonings of 2018.

The former prime minister told the BBC she hopes friends and family of Wiltshire woman Dawn Sturgess, who was killed after coming into contact with the Russian-engineered nerve agent, “will take some comfort” from the probe into her death, set to start on October 14.

Ms Sturgess, 44, died after coming into contact with a discarded perfume bottle which had housed the chemical weapon in Amesbury in July 2018.

Her contact with the Novichok nerve agent followed the attempted murder of former spy Sergei 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, who had unwittingly given her the bottle containing the killer nerve agent.

In an interview with the BBC’s Crime Next Door: Salisbury Poisonings podcast, Baroness May said of the inquiry: “I would hope by the end of it the family and friends of Dawn Sturgess feel it has got to the truth.”

The former British leader said, however, that “closure to all the people affected would only finally come with justice, and that justice is highly unlikely to happen”.

An international arrest warrant was issued for three Russian men thought to be involved in the attacks on British soil, but as the Russian constitution does not allow the extradition of its citizens it is unlikely they will ever stand trial.

Baroness May also said the Russians accused of executing the attack acted with “utter recklessness”.

“You felt they just didn’t care about anything,” she said.

The Skripals will not give evidence at the inquiry next week over fears for their safety.

It comes as Wiltshire Police said people in Salisbury city centre can expect to see an increased police presence for the duration of the hearing.

They added that there is “no current intelligence to suggest there is any risk to the wider public”.

Wiltshire Police and Crime Commissioner Philip Wilkinson said: “Residents will see an increased, but proportionate policing presence in, and around, Salisbury city centre and the Guildhall while the inquiry sits here.

“This is a precautionary measure only, with nothing to suggest any wider risk to our communities, to enable Wiltshire Police to keep all our communities safe.”

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

They were, however, excused from doing so in a subsequent ruling, with the relevant judgement citing an “overwhelming risk” of another physical attack on their lives.

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