The Russian embassy published a list of 14 questions on Saturday over the nerve agent attack on 4 March.
The first question asks: “Why has Russia been denied consular access to the two Russian nationals, Sergei and Yulia Skripal, that have become crime victims in the British territory?”
The embassy also repeatedly queries France’s “involvement” in the investigation and asks if Novichok – the nerve agent the UK says was used in the attack – could have been “researched, developed or produced in the UK”.
Russia, which rejects UK accusations of orchestrating the poisoning, had previously released a list of 27 questions about the case, including queries about the condition of the two victims.
Russia has insisted on the right to see the 33-year-old after it emerged she was improving rapidly.
An FCO spokeswoman said: “We are considering requests for consular access in line with our obligations under international and domestic law, including the rights and wishes of Yulia Skripal.”
The UK has expelled 23 Russian diplomats in the wake of the poisoning of Mr Skripal, 66, and his daughter. A number of other countries followed suit, including America, Canada, Australia and more than a dozen EU nations.
Here is the full list of questions:
1. Why has Russia been denied consular access to the two Russian nationals, Sergei and Yulia Skripal, that have become crime victims in the British territory?
2. What specific antidotes were administered to Mr and Ms Skripal, and in which form? How were those antidotes available for the medical staff on the site of the incident?
3. On what grounds has France been involved in technical cooperation with regard to the investigation of an incident in which Russian nationals had suffered?
4. Has the United Kingdom informed the OPCW (Organisation for the Prohibition of Chemical Weapons) of France’s involvement in the investigation?
5. How is France relevant to the incident with two Russian nationals in the UK?
6. What British procedural rules allow a foreign state to be involved in a domestic investigation?
7. What evidence has been passed to France for studying and/or for a French investigation?
8. Were French experts present when biological material was taken from Mr and Ms Skripal?
9. Have French experts studied biological material taken from Mr and Ms Skripal, and at which laboratories?
10. Does the UK possess the results of the French investigation?
11. Have the results of the French investigation been passed to the OPCW Technical Secretariat?
12. On the basis of which characteristics (“markers”) has it been ascertained that the substance used in Salisbury “originated from Russia”?
13. Does the UK possess reference samples of the military-grade poisonous substance that British representatives identify as “Novichok”?
14. Has the substance identified by British representatives as “Novichok” or analogous substances been researched, developed or produced in the UK?