Down a trench in Ukraine's Donbas region, Dima admits it took him time to adjust to the sounds of war, to living with fellow soldiers and to the flies everywhere.

Now, the 25-year-old soldier with an easy smile is quietly confident and says everything is fine, despite the constant boom of artillery.

His nickname "Moryak" (Sailor) is scrawled on his uniform, along with the slogans used by soldiers at war: "Born to Hunt" and "Si vis pacum para bellum" (If you want peace, prepare for war).

After serving on the frontline in the Sumy and Kharkiv regions in northern Ukraine, Dima was deployed to a position in the Izyum region.

The trench in the Donbas region measures several dozen metres -- a labyrinth littered with pickaxes and underground shelters where the men sleep
The trench in the Donbas region measures several dozen metres -- a labyrinth littered with pickaxes and underground shelters where the men sleep AFP / MIGUEL MEDINA

This part of the frontline lies to the northwest of Kramatorsk -- the administrative centre of Donbas, an industrial region Russian troops are attempting to conquer.

Since he arrived, Dima has been digging into the black earth -- like everyone else in his unit.

Their trench measures several dozen metres -- a labyrinth littered with shovels and pickaxes and underground shelters where the men sleep.

"We hide when they shell, we dig when it's calm," says one soldier.

This frontline trench in the Donbas stands against Russian efforts to seize control of the Ukrainian region
This frontline trench in the Donbas stands against Russian efforts to seize control of the Ukrainian region AFP / MIGUEL MEDINA

Russian forces are just a few kilometres away.

"No pasaran!", exclaimed the head of the unit, Ahil, an experienced soldier of few words.

Ahil, the head of the unit,  says he has been fighting in the Donbas since 2014 when Russia-backed separatists first seized control of part of the territory
Ahil, the head of the unit, says he has been fighting in the Donbas since 2014 when Russia-backed separatists first seized control of part of the territory AFP / MIGUEL MEDINA

Asked how many men are in the unit, he replies: "The number we need."

The situation? "It could be worse". Weapons? "We never have enough". Morale? "Good".

Ahil says he has been fighting in the Donbas since 2014 when Russia-backed separatists first seized control of part of the territory.

He believes the situation now is completely different.

Map of eastern Ukraine showing the Donetsk and Lugansk regions which formed the Donbas
Map of eastern Ukraine showing the Donetsk and Lugansk regions which formed the Donbas AFP / Kenan AUGEARD

"Today, there is total war," says the soldier, hoping to "rest when it's all over".

"If I get to that point," he adds.

Before saying goodbye to a group of journalists, Ahil removes his helmet to reveal a shaved head except for a large bunch of hair on one side.

"It's a Cossack haircut. It fits the moment," he laughs.

A Tochka-U missile lies in the courtyard of a nearby house
A Tochka-U missile lies in the courtyard of a nearby house AFP / MIGUEL MEDINA

This part of the frontline has been one of the most active since Russia invaded on February 24 but it has become calmer in recent weeks as Russian troops attempt to advance elsewhere.

"This place has been one of the bloodiest," admits "Grizzly", another commander with a beard and tattoos who wears a woolly hat despite the heat.

"The previous unit lost many men. Up to 40 percent of them remain here forever," he says.

Dima has also seen his comrades fall in battle.

"It's sad of course when it happens to friends you share a life with in the trenches.

"But at the same time it motivates you even more to remove these bastards that nobody wants here," he says

Asked if he thinks about death, he replies: "Of course, I think regularly that it's maybe my last cup of tea or the last time I go to bed."

Outside the trench, the countryside stretches out in a landscape that would be magnificent except for the vast scorched fields.

Unexploded ordinance lies on the roads, which are pockmarked with craters and lined with burnt out vehicles.

Some rare military vehicles can be seen. A T-72 tank kicks up a cloud of stones and dust as it turns.

A few kilometres back, the brigade's headquarters are set up in an abandoned farm.

Chickens wander through the ruins, a cat sleeps on an abandoned chair and bees fly out from their untended hives.

A Tochka-U missile lies in the courtyard.

At the bottom of a small staircase, the officer in charge is at work in a 15-square-metre room full of maps and radios to communicate with the positions.

Three men lie in the darkness of the room, staring at their phones absent-mindedly.

Oleksandr, the officer, a jovial man of 34, says the situation is "under control".

"We have been here since the end of April and, after several attempts by the enemy to advance, we are the ones advancing, kilometre by kilometre."

The aim? "Total victory". Asked if he could envisage a ceasefire, he replies: "No, no, no".