Britain has sanctioned Russia's GRU military intelligence agency and summoned the Russian ambassador after an inquiry found President Vladimir Putin authorised a nerve agent attack in England seven years ago, Associated Press reported on December 4.

The UK government said the entire GRU was being targeted for reckless actions including the 2018 Salisbury attack on Sergei Skripal, a former Russian intelligence officer who had spied for Britain. Skripal was jailed in Russia in 2006 before being freed in a prisoner exchange four years later and relocating to England.

Skripal and his daughter Yulia fell seriously ill in March 2018 after contact with Novichok, a military-grade nerve agent that had been applied to his front door handle. A police officer responding to the incident was also poisoned. All three recovered.

Months later, Dawn Sturgess and her partner Charlie Rowley were poisoned after discovering an abandoned perfume bottle that contained the same substance. The 44-year-old Sturgess applied the contents to her wrist and died within days. Rowley survived.

Anthony Hughes, a former Supreme Court justice who conducted an inquiry into the death, determined that the assassination attempt on Skripal required approval at the highest level of the Russian government, specifically from Putin.

Sturgess was described in the inquiry's findings as an innocent victim of a state-sponsored assassination attempt using a highly toxic chemical weapon on the streets of an English city.

The Kremlin has consistently denied any role in the poisonings. Putin publicly dismissed Skripal as worthless to Russian interests.

Relatives of Sturgess said she died because of Russia's attempt to kill Skripal but also criticised British security services for failing to properly assess the threat facing the former spy, arguing this failure endangered the public.

Eight alleged GRU cyber operatives were also named in the sanctions for reportedly targeting Yulia Skripal with malicious software years before the physical attack.

Three suspected GRU officers have been charged over the Skripal poisoning but remain in Russia, which has no extradition treaty with Britain.

Prime Minister Keir Starmer described the inquiry's conclusions as a stark reminder of the Kremlin's indifference to civilian lives.

Novichok nerve agents were developed by the Soviet Union during the Cold War. Western intelligence agencies maintain the substance was produced exclusively in Russia.