"We are seriously concerned with the media reporting possible problems with Evgeny Nikulin’s 'mental condition'. If this is the case, all the blame for deterioration of his health falls on the US authorities," the embassy wrote on Facebook.
The Russian diplomats said, citing the media reports and Nikulin's lawyer, that the Russian citizen was "restricted in walks, not allowed to call his relatives."
"As we know from the press, even during his two-year detention in a Prague prison, his defense disclosed information that the FBI – Federal Bureau of Investigation had offered Evgeny Nikulin an extradition to the US, where he was expected to discredit [US PResident] Donald Trump’s election campaign through the media by claiming to have hacked the DNC servers. In exchange for this perjury, he was promised to be cleared of all charges, a monetary compensation and American citizenship," the embassy said.
The diplomats added, citing Nikulin's lawyers, that the special services had tried to influence him psychologically so that he would "strike a deal with the U.S. intelligence services."
"As we can see now, student Maria Butina, who was arrested on groundless charges, has to suffer similar methods," the embassy pointed out.
The diplomats criticized the recent statement of [defense lawyer] Arkady Bukh, who suggested that the Russian embassy could pose a threat to Nikulin. They pointed out that the lawyer had earlier told them about his concerns regarding his clients' well-being in the United States.
"The Embassy closely monitors the situation with the rights of imprisoned Russian citizens in the US We will continue this work, paying zero attention to all kinds of taunts and innuendos," the diplomats said.
However, Bukh told Sputnik that his words had been "somewhat misinterpreted" by the US media.
"In fact, I confirm once again that I did tell the [Russian] embassy that I have no trust in the US system regarding the psychiatric care, especially state-funded. I told them that at the time, and I stand by my words. I really believe that Nikulin might end up, as they [the Embassy] put it, 'healed to death'," the lawyer said.
Bukh added that he did not say that the embassy might pose a threat to Nikulin.
"This is the way the US media interpreted it during the interview. I have a lot of positivity, a lot of trust toward the Russian Embassy and Russia, in particular. But the threats against a client in highly publicized, high profile cases are quite prominent," the lawyer said.
Bukh added that such threats could come from different sides: from the US government, but also from other interested parties.
"At the same time, I have no accusations, grievances or any reasons to think badly of the Russian Embassy," the lawyer stressed.
Nikulin pleaded not guilty to the US charges against him.
Butina was detained in the United States in mid-July on suspicion of espionage and pleaded not guilty during court hearings. The judge ruled that she should be arrested. Her next hearing is scheduled for September 10.