The Organisation for the Prohibition of Chemical Weapons – an international chemical weapons watchdog – confirmed on Thursday the United Kingdom’s findings on the nerve agent used to poison a former Russian spy. While the agency did not name the nerve agent as Russia-made novichok, it said it agreed with the UK’s analysis, the BBC reported.

A team from the organisation visited the United Kingdom on March 19. It collected blood samples from former Russian spy Sergei Skripal, his daughter Yulia Skripal and Detective Sergeant Nick Bailey, the police officer first on the scene in Salisbury, England, where the Skripals were found unconscious on a bench.

The agency has not made its report public yet. But according to media reports, it has identified the toxic chemical used to poison the Skripals by its complex formula and said it was of “high purity”. It confirms Britain’s claim that the kind of expertise with which the nerve agent was manufactured indicated that a national government had a hand in it, The New York Times reported.

Meanwhile, the London Metropolitan Police on Monday said Yulia Skripal, who was discharged from hospital on Tuesday, had turned down Russia’s offer of consular assistance.

“I have been made aware of my specific contacts at the Russian Embassy, who have kindly offered me their assistance in any way they can,” she was quoted as saying in the police statement. “At the moment, I do not wish to avail myself of their services, but if I change my mind, I know how to contact them.”

On March 4, the father and daughter were found unconscious on a park bench outside a shopping centre in Salisbury. The poisoning has led to a major diplomatic controversy globally. The UK and its allies, including the European Union and the North Atlantic Treaty Organisation, have accused Moscow of being involved in the incident and expelled 23 Russian diplomats from its territory. Maintaining innocence, Russia responded by expelling an equal number of British diplomats.