Wagner mercenaries buttress Russia's battered army

As Russia's invasion force in Ukraine has been battered by Kiev's counter-offensive, one section of front around Bakhmut is bucking the trend thanks to the Wagner mercenary group, which experts say is now a vital cog in Moscow's military machine.

Deployed in recent years in Syria, Mali and the Central African Republic, "Wagner... is right now proving to be the most capable infantry that the Russian army has" in Ukraine, said Philip Wasielewski, a researcher at the US-based Foreign Policy Research Institute.

"However, it's not a high bar because of the poor performance of the Russian army," he added.

Kiev's forces have scored spectacular advances in the northeast around Kharkiv and in the south towards Kherson in recent weeks.

But Ukrainian troops in Bakhmut, an eastern city in Donetsk where Russia has been advancing, say they face Wagner troops across the front lines.

The Kremlin has always denied any ties with private military groups, and Wagner has no legal entity in Russia, where mercenary companies are illegal.

That fiction was partly dispelled in late September, when Yevgeny Prigozhin -- a businessman close to President Vladimir Putin and a fellow Saint Petersburg native -- acknowledged founding the company in 2014, calling its fighters "pillars of our motherland".

Sent to support the Assad regime in Syria and into Libya, they have repeatedly been accused of atrocities against civilians on current deployments in Mali and the CAR.

– 'Musicians' in Wagner's 'orchestra' –

There was little sign of Wagner presence in Ukraine early on in Russia's assault on its neighbour.

Recently, however, "they've become more and more visible, and almost affiliated with the Russian state," said Tracey German, a lecturer in defence studies at King's College London.

Wagner's fighters "have been used as a force multiplier for Russia," she said.

One advantage of using mercenaries is that "it allows the Kremlin to avoid having to state casualties" as it would with regular troops -- a boon for a government loath to reveal losses believed by Western sources to mount into the tens of thousands.

Wagner-linked accounts have also been spreading Moscow's propaganda on social media, claiming to be fighting to "liberate the Donbas" and drive out Ukrainian "Nazis".

But the group also strives to set itself apart with imagery and language.

Sporting its logo of a death's head in red crosshairs, members call themselves "musicians" belonging to Wagner's "orchestra".

And they are no longer shy about talking up the role they are playing in Ukraine fighting.

Increased use and spotlighting of the mercenaries is "reflective of wider breakdowns in the Russian military and amongst Russian military leadership," said Karolina Hird of the US-based Institute for the Study of War.

"We've seen in the past months this new rhetoric, originating from Wagner gains, that basically Wagner has become the Kremlin's premier strike force," she added.

– Ground down –

That could be a sign of tensions within the Russian elite, where the regular army no longer commands the same respect, Hird said.

"It seems like (Wagner boss) Prigozhin is trying to curry favour with the Kremlin through pushing his own influence and the gains that his troops have made."

The close Putin ally on Tuesday announced the construction of a line of fortifications in the eastern Lugansk region, one of the four whose "annexation" Moscow announced in September.

He went on to boast that the defence line would not be "needed" because "the presence of a Wagner unit at the front line is already an impregnable wall" in itself.

Researcher Wasielewski said that Wagner's advantages include "a little better leadership" thanks to its recruitment among former special forces troops, as well as the fact that "they are paid as promised".

"However, the question is how long that can be maintained," he added.

"As the fighting and heavy casualties go on... the long-term employees of Wagner will die or be wounded... you'll have less and less of that background, less and less of that experience, less and less of that leadership for the younger or the newer Wagner recruits."

A video that circulated online in September appeared to show Prigozhin promising a crowd of prison camp inmates pardons if they agreed to fight for Wagner in Ukraine.

Wagner's chest-beating may be "a way of addressing its own recruitment problems," suggested Yohann Michel, a researcher at the International Institute for Strategic Studies in London.

"Whatever happens, Wagner won't be able to advance without the rest of the army, there aren't enough of them to mount a successful large offensive," he added.