But drones, despite being responsible for the lion's share of Russian casualties, were not enough, he argued.

"I cannot transform a million-strong army to drones in two months and say: now we fight like this."

Syrskyi said he was not at war with the defence ministry but with Russia. But while he mounts his defence against a host of critics, speculation has fallen on who Zelensky might choose to replace him.

The candidates include Mykhailo Drapatyi, commander of the Joint Forces, Andriy Bilekskyi, commander of the Third Army Corps, Oleh Apostol, commander of the Airborne Assault Forces and Ihor Obolenskyi, commander of the National Guard Corps.

All have distinguished military records, but crucially all are from a much younger generation of officers. At 46, Biletskyi is the oldest while Apostol and Obolenskyi are both 39.

At just 35, the youngest possible candidate is Brig Gen Denys Prokopenko, another National guard commander, whose "Azov" Regiment, while politically controversial for its alleged far-right connections, achieved near mythic status during the bitter siege of the southern port city of Mariupol in 2022.

Held as a prisoner of war by Russia following the collapse of the city, Prokopenko returned to Ukraine as part of a prisoner exchange in July 2023, quickly resuming his command despite Russian demands that he remain outside the country until the war was over.

Zelensky says he is still working out "what adjustments need to be made to Ukraine's defence strategy" and has thanked everyone "for their openness, honesty and substantive contributions".

With Russia expected to resume its attacks on Ukraine's energy infrastructure this autumn, the president says "Ukraine must enter August as strong as possible".

As the protests fall silent for now, the country waits for the president to make a series of possibly fateful decisions.