Dmitry Kozak, who previously served as deputy chief of staff to President Vladimir Putin, submitted a letter to the president earlier this year in which he criticized Russia’s invasion of Ukraine in 2022. This information was revealed by the investigative outlet Agentstvo, citing sources familiar with the situation.

According to one insider, Kozak, a long-time ally of Putin, does not believe that his comments upset the president and is “hoping to meet with him again soon.” Another source stated that the letter voiced his opinions on the conflict “in very strong terms,” and it was drafted concurrently with his resignation letter, which was submitted in mid-September.

Agentstvo has not disclosed any excerpts from the letter, and The Moscow Times has not been able to independently verify its existence.

Sources indicated that since stepping down, Kozak has been traveling frequently to Israel, not due to safety concerns, but for medical treatment.

In August, The New York Times reported that Kozak had lost favor with Putin after expressing opposition to the war. He reportedly advised against escalating the conflict just three days before the full-scale invasion and suggested an early resolution, which Putin rejected, leading to Kozak being stripped of his responsibilities related to Ukraine.

Previously seen as a significant behind-the-scenes figure, Kozak has kept a low profile since leaving the Kremlin, with many of his roles reportedly transferred to Sergei Kiriyenko, the influential first deputy chief of staff.

Kozak was born in Ukraine’s Kirovohrad region, which was part of the Soviet Union at the time, and began his career with legal positions in St. Petersburg while Putin was in the mayor’s office. He entered federal government service in 1999 and transitioned to the Kremlin following Putin’s election in 2000.