THE SNP’s international affairs spokesman, Stephen Gethins MP, has written to the Russian Consulate in Edinburgh to underline that diplomats must be “open to speaking to police” investigating the Skripal nerve agent.

The letter also raises concerns about Russian military interventions in Ukraine and the annexation of Crimea, as well as “attacks on human rights” by the Russian Government against its own people.

The email from Gethins to the consulate is a significant escalation of diplomatic tensions between the SNP and Russian diplomats in Scotland, and follows First Minister Nicola Sturgeon’s condemnation of Russia over the use of the Novichok nerve agent in the UK.

Gethins wrote to the consulate after an attaché to the Russian consulate sent the MP an email from the Sunday Herald to the Consul General Andrey Pritsepov which asked him to respond to comments by Gethins which said police officers investigating the Skripal attack “should have access to staff at the Russian embassy and the consulate”.

The Consul General did not respond to the Sunday Herald’s request for a comment but on March 13 attaché Magomet Zyazikov forwarded the email to Gethins with the message: “Please find the letter below for your information.”

Responding, Gethins said: “I hope that Russian officials would be open to speaking to the police if they consider that was helpful to the case. That investigation into this grave attack must be given the seriousness it is due.”

Last week Stephen Gethins told the Sunday Herald the attempted murder of ex-spy Skripal and his daughter bears “all the hallmarks of state involvement”.

“The Russian authorities have previously shown that they are perfectly willing to step outside international norms of behaviour and the Russian government has disrespected the rule of law in both its own country and its neighbours,” said Gethins.

“I would urge the UK authorities to investigate fully these and any other attacks of this kind. Those investigating should be able to conduct their enquiries thoroughly, which would include access to staff at the Russian Embassy and the Consulate in Edinburgh.”

The Sunday Herald has contacted Consul General Andrey Pritsepov several times through attaché Magomet Zyazikov.

The last email from Zyzakov was sent on March 7, when he indicated that Pritsepov would agree to an interview on March 27.

The Sunday Herald confirmed the interview, which included an opportunity to respond to Gethins’ comments about the Skripal attack, but there has been no response from the Consulate since, despite further attempts to contact by email and by phone.