Ukrainian journalist Roman Sushchenko, who was arrested in Russia and whom Moscow believes to be a colonel of the Ukrainian Defense Ministry's intelligence service, has been transferred to a two-man cell, his public defender Mark Feygin has said.

"Sushchenko was transferred from the solitary cell to which he was moved following my disbarment to a two-man cell. Now he has a cellmate. And before that, they said that the transfer to the solitary cell was in the interest of security," Feygin wrote on his Facebook account on Saturday.

He also posted a photocopy of the Moscow City Court's decision permitting him to visit Sushchenko "alongside a lawyer in the capacity of another person defending Sushchenko's interests."

On April 25, the Ukrainian Foreign Ministry sent a note of protest to the Russian side due to the change of Sushchenko's incarceration conditions.

"Obvious psychological pressure, particularly in light of the replacement of the lawyer," Ukrainian Foreign Ministry spokeswoman Mariana Betsa said on Twitter.

Feygin was disbarred by the Moscow Chamber of Lawyers on April 24. In addition, Sushchenko's family was urgently advised to get a new lawyer, he said.

Sushchenko's detention "during an act of espionage" in Moscow was reported on October 3, 2016. According to the Federal Security Service (FSB), Sushchenko, as a staff officer of the Ukrainian Defense Ministry's Main Intelligence Directorate with the military rank of colonel, collected state secrets about activities of the military and the Russian Guard.

Defender Feygin said that Sushchenko, who spent six years in Paris as a correspondent for the Ukrinform news agency, had repeatedly visited Russia and was there for personal reasons at the time he was detained. His relatives live in Russia.

Kyiv described Sushchenko's detention as a provocation and the espionage charges brought against him as far-fetched.