The next phase of the Russian military campaign in Ukraine could begin in the next few days, according to two senior U.S. defense officials, and Ukraine is rapidly running through artillery and artillery rounds.
The officials said a U.S. assessment is the Russian military could begin moving some of its forces back into Ukraine as soon as this weekend or early next week.
Russian troops retreated from around Kyiv and northern Ukraine about two weeks ago, moving north into Belarus and Russia.
At the time, U.S. officials assessed the Russians intended to re-group and then begin another invasion, focusing on the Donbas region and southeastern Ukraine
But now U.S. officials believe Russia may move troops back into Ukraine and begin the offensive before all the Russian troops are ready to fight again, a senior defense official said.
Ukrainians running through artillery rounds
Even as the Russian military has been preparing for the next phase of the invasion, Russia and Ukraine have continued fighting in the east and south.
During that time the Ukrainian military has been expending several thousand artillery shells every single day, a senior defense official said.
This week the Biden administration announced it was sending 40,000 artillery rounds and 18 155mm howitzers to Ukraine. But with the Ukrainian military using thousands per day, that 40,000 will only last a little over one week, the official explained. U.S. officials are working the phones to convince allies to send more artillery and ammunition to Ukraine so it doesn’t run out when the offensive ramps up.
Russian troops are likely to try to encircle Ukrainian troops arrayed along the border between Donbas and the rest of Ukraine in this coming offensive — a military move called a double envelopment. The Russian military relied heavily on long-range fire — cruise missiles, long-range artillery, airstrikes — in the early weeks of its assault on Ukraine, but the main weapons of this new offensive will likely be artillery and short-range missiles, a senior defense official said.
The Ukrainian military has some artillery but most of it is outdated, much is beaten up, and some has been destroyed by the Russians. The newer howitzers from the U.S. will be more durable than the existing Ukrainian artillery, the official said, but the world has to keep supplying Ukraine with munitions so it can stay in the fight.
The Russians have already begun shaping operations in the southeast, preparing the area around Donbas for a coming Russian ground invasion, according to a senior defense official. On Thursday a senior defense official said Russia has begun moving equipment into western Russia in preparation for the offensive, including helicopters that are now staged for insertion into Ukraine.
Courtney Kube is a correspondent covering national security and the military for the NBC News Investigative Unit.