UK town to reopen after nerve agent attack

The UK town of Salisbury, which has been sealed off for three months following a nerve agent attack, is preparing to reopen.

Military personnel in Salisbury as police examine 200 witnesses and 240 pieces of evidence. Source: AAP

Businesses in Salisbury are preparing to reopen as the British city takes a "massive step" in its recovery from the nerve agent attack.

Wiltshire Council said the thoroughfare would be open on Saturday morning, nearly 11 weeks after the incident that thrust the cathedral city into the centre of a global diplomatic crisis.

Former Russian spy Sergei Skripal and his daughter Yulia were found unconscious from the effects of the military nerve agent Novichok on a bench in area on March 4.

Swathes of the city were sealed off as investigators moved in before a massive decontamination operation began.

The UK Environment Department announced it had handed back the area from government control on Monday after an "extensive clean-up".

Alistair Cunningham, head of the council's recovery effort, said the reopening of the shopping precinct represents a "massive step the recovery for this beautiful city".

"The Maltings site has undergone thorough testing and clean-up work by world-class specialists, and the public can be reassured that any traces of nerve agent that may have been present have been removed and the site presents no risk to public health."

Army officers remove the bench, where Sergei Skripal and his daughter were found, in Salisbury. Source: AAP

Businesses in the Maltings and around Salisbury have been adversely affected by the incident as some shoppers avoided the area over health and safety concerns.

Last week, ministers praised the "resilience" of Salisbury residents in the face of disruption, which they blamed on "Russia's reckless actions".

Prime Minister Theresa May's official spokesman said police had released all sites for decontamination, except for the Skripal house, and the priority was making the sites safe so "Salisbury can get back to normal".

Moscow has repeatedly denied responsibility for the attack on the Skripals, and on Friday Vladimir Putin questioned the UK's explanation around their poisoning.

The Russian president said the version of events "is not possible" as victims of a military grade agent would have died "immediately".