Yulia Skripal, who was poisoned along with her former double-agent father Sergei in Salisbury last month, has been discharged from hospital.
The 33-year-old Russian national had spent more than a month in hospital after coming into contact with the military-grade nerve agent Novichok.
She is reported to have been released on Monday (April 9) and taken to a secure location.
Both were fighting for their lives when they were discovered unconscious on a park bench on March 4.
On Friday (April 6), Salisbury District Hospital doctors said 66-year-old Skripal was "responding well to treatment, improving rapidly and no longer in a critical condition".
However the Foreign Office say it is likely the pair will have "ongoing medical needs".
Moscow has denied responsibility for the poisoning but the incident has plunged diplomatic relations between Russia and the West into the deep freeze.
Boris Johnson used a Sunday Times article to accuse Jeremy Corbyn of lending "false credibility" to Moscow by not blaming the Russian state unequivocally over the incident.
Johnson also said the Kremlin had released a "torrent of absurdity" following the attack.