Chechen leader Ramzan Kadyrov slammed the Russian military's recent prohibition of wearing beards, joining the mercenary group Wagner's leader Yevgeny Prigozhin, in criticizing military leadership.

In an interview with the RBC news site on Wednesday, Viktor Sobolev, a retired lieutenant general and member of Russia's parliament, defended the ban on beards, personal smartphones and tablets as an "elementary part of military discipline."

Writing on Telegram, the bearded Kadyrov, who has talked up the role of his troops in Russia's war in Ukraine, wrote, "Apparently, Lieutenant General Viktor Sobolev has a lot of free time since he has nothing to do but re-reading the military code of conduct."

Kadyrov called Sobolev's comments "a clear provocation," saying that his mostly Muslim soldiers wore beards as part of their religious duty.

Wagner boss Prigozhin, whose rift with the defense establishment has become more public in the past week, called Sobolev's comments "absurd" and "archaisms from the 1960s."

Kadyrov and Prigozhin, whose forces in Ukraine operate largely autonomously of the high command, have become more outspoken in their criticism of the Russian military leadership since Moscow's armies suffered a string of cascading defeats in the autumn.

The two men have formed a tacit alliance, amplifying each other's criticism of the military top brass and calling for more vigorous prosecution of the war.