Soviet Poison Expert Backs U.K. Claims That Ex-Spy Was Hit With Nerve Agent He Invented

The U.K. is right to punish and blame Russia for the poisoning of an ex–double agent on English soil, one of the Russian developers of the Soviet Union's chemical arms has said.

The ex-Russian military intelligence officer, Sergey Skripal, was poisoned alongside his daughter last month by a substance that they are thought to have been exposed to in their home in Salisbury, England. British investigators have quickly pointed the finger at Russia, identifying the chemical used as a member of the family known as novichok, which was developed by the Soviet Union during the Cold War. The Russian government has denied orchestrating the poisoning and deflected the accusations to other countries it says are able to produce the military-grade substance.

Related: Guinea pigs and cat of poisoned spy Skripal are dead

In denying complicity, Russia's Ambassador to the U.K. Alexander Yakovenko said last week that Russia had never produced the so-called novichok, and it was "a creation of some other countries and some scientists."

A bench covered in a protective tent at The Maltings shopping center in Salisbury, southern England, on March 15 as investigations continue after a man and woman were apparently poisoned in a nerve agent attack on March 4. One of the nerve agent's purported developers has voiced his support for the British government's handling of Russia. Daniel Leal-Olivas/AFP/Getty Images

One of the Russians who worked on the Soviet chemical weapons program from the 1970s until the 1990s, Vladimir Uglev has confidently declared that what incapacitated Skripal was the substance he developed in 1975, ranked as part of the novichok family.

"I have no doubt that it was precisely A-234 which was used!" Uglev told the Financial Times in comments sent via email from his retirement home on the Black Sea coast. The chemist warned, however, that determining with absolute certainty where the substance had been produced was not possible. The Organisation for the Prohibition of Chemical Weapons is expected to finalize its analysis of the matter this week.

Russia has pointed to the fact that the British allegations lacked certainty about the compound's origin as a reason to criticize an international wave of sanctions that have hit its diplomats in Europe and the U.S. as punishment for the poisoning. The U.K., U.S. and over 20 partnering countries kicked out more than 100 Russian diplomats as a punitive move following Skripal's poisoning. Uglev said he supported London's actions, adding that definitive, chemical proof in these matters was unlikely. Instead, he criticized what he believed to be the tactics of Russian President Vladimir Putin, his administration and his allies in the security services.

"As a Russian citizen, I do not accept the great-power chauvinism fanned by the regime of Kremlin-Lubyanka thieves and killers, and therefore fully understand and support the policy of the British government towards Russia," Uglev said. Putin once headed the federal security services at their headquarters in Lubyanka Square, before moving into politics. "At the same time, as a professional chemist, I perfectly understand that we will not get 100 percent proof of the guilt of the Kremlin-Lubyanka killers, neither from the English specialists, nor from the experts of the OPCW," Uglev added.

Skripal is apparently on the mend after a month in recovery, according to hospital officials in Salisbury, who confirmed last week that the ex-spy is no longer in critical condition.