President Volodymyr Zelenskiy dismissed the secretary of Ukraine's national security council and replaced him with the head of his foreign spy agency on Tuesday in a new shake-up that follows the overhaul of the military high command last month.
No reason for the changes was given in a series of blandly worded decrees that were published on the president's website more than two years into Russia's full-scale invasion.
Oleksiy Danilov, the outgoing secretary of the National Security and Defence Council, had held his position since October 2019, just months after Zelenskiy took office.
Zelenskiy, speaking later in his nightly video address, said Danilov was being transferred to new duties, with details to be made public later.
He gave no reason for Danilov's removal but said he expected "a strengthening of our state's strategic capabilities to forecast and influence the processes upon which our national security depends.
"The strengthening of Ukraine and the renewal of our state system in all sectors will continue."
Zelenskiy appointed Oleksandr Lytvynenko, 51, head of the foreign intelligence service, who has no almost public profile whatsoever, to head the council.
In his address, Zelenskiy said his appointee would combine experience as an intelligence chief with the tasks Ukraine faced in terms of security and defence.
The council has a coordinating role on issues of national security and defence under the president and comprises the country's top political, security and defence chiefs.
Ukraine is battling to keep up its war effort and hold the line against attacking Russian forces in the east with its vital U.S. ally proving unable to deliver military assistance due to Republican congressional resistance.
Military analysts are also raising questions about the depth and strength of Ukrainian fortifications and regard manpower levels as another challenge. Russia has a much larger population than Ukraine and is on the offensive.
Zelenskiy's decrees named Oleh Ivashchenko, a deputy chief of the Ukrainian military spy agency who also has no public profile, as the new foreign intelligence chief.
The Ukrainian leader replaced the head of the armed forces in February. Swathes of the military's top brass were also cleared out and replaced.