Ukrainian President Volodymyr Zelenskyy has appointed Oleksandr Pavliuk, former first deputy defence minister, as the new commander of Ukraine's ground forces, according to a decree published on Sunday.
Mr Pavliuk, a Lt Gen who served in the ministry role for a year, replaces Col Gen Oleksandr Syrskyi after he was this week appointed as commander of Ukraine's armed forces.
On Saturday, Mr Zelenskyy announced five other senior military appointments, filling out a rebooted team to bolster Ukraine's defence against Russia's nearly two-year-old full-scale invasion.
Mr Zelenskyy's decision to remove Valeriy Zaluzhny as chief of Ukraine's armed forces on Thursday came after months of speculation about tensions between the two men.
The sacking of Mr Zaluzhny, a popular figure, was widely viewed as a risky move due to uncertainties caused by a shortage in men and equipment.
The war-torn country made few battlefield gains throughout the past year and also faces disruption in military aid from the US, its biggest backer.
Russian troops are tightening their grip around the embattled town of Avdiivka, where Ukrainian troops are dug in. Elsewhere on the eastern front, Moscow's troops are building offensive pressure.
During a visit to Washington earlier this week, German Chancellor Olaf Scholz stood alongside US President Joe Biden to urge US lawmakers to approve a long-delayed military aid package for Ukraine, warning that Kyiv could not hold off Russia's invasion without it.
“Without the support of the United States and without the support of European states, Ukraine would have not a chance to defend its own country,” Mr Scholz warned. Germany is the second largest supporter of Ukraine's military behind the US.
Ukraine's military said Russia launched drone attacks on Kyiv and southern Ukraine overnight, injuring at least one civilian and damaging a gas pipeline and residential buildings in the river and seaport of Mykolaiv.
Ukraine's Air Force said its air defence systems destroyed 40 out of 45 Russia-launched Shahed attack drones overnight.
“The air alert in the capital lasted almost two hours,” Serhiy Popko, the head of Kyiv's military administration, said.
He added that over Kyiv all the drones were shot down on their approach. According to preliminary information, there were no casualties nor destruction in or near the capital. Skies over Kyiv were declared clear soon before 4am (0200 GMT).
Both Russia and Ukraine have increased their air attacks away from the front line in recent months, targeting each other's critical energy, military and transport infrastructure.