The Times writes that the British security services have located in Russia the place where they believe that the neurotoxic substance Novitsok was prepared, which was used against Sergei and Yulia Skripal.
It is the state research base in Sikkhani in southwestern Russia, which is described as the equivalent of the scientific laboratory of the British Ministry of Defense in Porton Down.
The newspaper also reports that the British side has told international allies about the role of this laboratory in the case, which seems to have counted in the decision of more than 25 countries to deport dozens of Russian diplomats.
The presentation of the findings by the British to the allies is said to have included evidence that Sikhani's laboratory had been investigating for the past decade whether the Novitsok-type substances could be used for assassinations abroad.
It is also reported that the chemicals stored in this research base were much smaller than would be required to make mass-produced chemical weapons, which has led the British to conclude that the chemicals there were intended for targeted attacks.
However, it is noted that on Thursday the Russian ambassador in London stated categorically that his country has never prepared substances of the Novitsok family.
According to the same Times report, the security services are urging the government to reveal more of the evidence in its possession, seeing that Moscow is strongly opposed to the propaganda battle.
At yesterday's emergency meeting of the UN Security Council requested by Russia, a spokesman for the Russian government warned Britain that it was "playing with fire". The British representative objected that she does not accept ethics lessons from a country that obstructs the investigation into the use of chemical weapons in Syria.