Ukraine has moved to a defensive posture, its newly-appointed army chief has said, as Russia advances along the entire front line.

Col Gen Oleksandr Syrskyi vowed to “inflict maximum losses” on Russian forces in the attempt to contain their offensive.

“At this time, the situation can be assessed as difficult. The enemy is now advancing along almost the entire front line, and we have moved from offensive operations to conducting a defensive operation,” Ukraine’s commander-in-chief told German broadcaster ZDF.

“The objective of our defence operation is to exhaust the enemy’s forces, inflict maximum losses on him, using our fortifications, our advantages in terms of technology, in terms of using unmanned aircraft, means of electronic warfare, and maintaining prepared defence lines.”

Col Gen Syrskyi was made the commander of the Ukrainian armed forces by president Volodymyr Zelensky in a significant military shake-up last week.

He inherited a perilous situation with Russian forces on the cusp of encircling Ukrainian forces in the Donetsk region town of Avdiivka.

Moscow is also advancing out of the nearby city of Bakhmut, which it captured after a brutal months-long battle last May, as well as further north in areas of the neighbouring Kharkiv region.

The first broadcast interview by Col Gen Syrskyi, who led the defence of Bakhmut, suggests his forces could attempt to snarl up Russian forces in Avdiivka in a similar campaign.

Kyiv has already dispatched two of its best units – the 47th Mechanised and 3rd Assault brigades – to defend the eastern city.

Battlefield footage shared on social media showed a gunner from the 3rd firing a M-2 heavy machine gun mounted on a US-supplied MaxxPro MRAP armoured fighting vehicle on the roads near the coke plant in the north of the city.

Russia managed to cross the main highway leading up to the industrial plant, severing Ukraine’s crucial line of ground communications between the stronghold and the rest of Avdiivka to the south.

Col Gen Syrskyi and Ukrainian defence minister Rustem Umerov visited a command post near the front-line city.

“The operational environment is extremely complex and stressful,” the general said in a post on the Telegram messaging app on Wednesday.

“The Russian occupiers continue to increase their efforts and have a numerical advantage in personnel. They do not count on losses and continue to use the tactics of ‘meat assaults’.”

He added: “We are doing everything possible to prevent the enemy from advancing deep into our territory and to hold the occupied positions. Despite the difficult situation, the defence forces of Ukraine inflict significant losses on the enemy.”

Ordinary Ukrainian troops have previously bemoaned his insistence to hold positions because of the heavy cost inflicted to their own forces on the ground.

In a bid to ease their concerns, Col Gen Syrskyi told troops in Avdiivka: “We are taking all possible measures to minimise our losses and save the lives of our soldiers.”