"However, for the benefit of its other titles and on-going academic publishing activity, it was agreed by Veruscript's board of directors that closing the services of this unique product was the most appropriate action at this time."

Commenting on the decision, Gleb Cheglakov and Nazik Ibraimova, co-founders of Veruscript, said: "We reiterate that we have not accepted, and would not consider, any form of state or agency funding under any circumstances, British or foreign.

"Any suggestion that we would seek influence in return for the very modest commercial and public investments we have made in academic forums, in any sector, is nonsensical and derisory.

"The whole point we have set up the business is to secure free speech and the open exchange of ideas, in an environment of total independence.

"We appreciate that there is heightened interest in Russia and its geopolitical status, but despite all parties disputing the allegations, and no evidence being found, Veruscript and its publication has found itself caught up in news and speculation about independent research, thinking and the University of Cambridge which is the exact opposite of what we have set out to achieve.

"We must though accept that the media interest in intelligence affairs, even their academic study in a mainly historical context, has made the launch publication in our series unfortunate in its subject matter, however excellent its merits.