“There will come a time when the tiny advances Russia is making become unsustainable in light of the costs and they will need a significant pause to regenerate capability,” said a senior Western official, speaking on condition of anonymity to discuss a sensitive issue…

According to chatter on Russian Telegram channels and Ukraine’s deputy defense minister Anna Malyar, the Russian military is under pressure to bring all of Luhansk under Russian control by Sunday, perhaps explaining the heightened momentum of the past week.

But the “creeping” advances are dependent almost entirely on the expenditure of vast quantities of ammunition, notably artillery shells, which are being fired at a rate almost no military in the world would be able to sustain for long, said the senior Western official…

Officials refuse to offer a time frame, but Britain’s Prime Minister Boris Johnson, citing British intelligence assessments, indicated this week that Russia would be able to continue to fight on only for the “next few months.” After that, “Russia could come to a point when there is no longer any forward momentum because it has exhausted its resources,” he told the German newspaper Sueddeutsche Zeitung in an interview.