Western defense officials say Ukraine has been employing agile insurgency tactics to disrupt Russia's invasion, and in the suburbs northwest and east of Kyiv, to push their adversaries back.
Hitting and ambushing Russian forces behind the contact lines with fast-moving units, often at night, has proven among its most effective field tactics and is adding to the logistical missteps the Russians still have not been able to overcome, military strategists say. They add that the tactics are also demoralizing Russian troops.
"They're doing a tremendous job," said Colonel John Barranco of the Atlantic Council, a New York-based think tank.
"The Ukrainians have developed a very competent military with good leadership at the lower level and they're motivated. And this is why, when I looked at the Russian forces deployed for the invasion, I thought, this doesn't seem like a well thought-out effort."
Barranco, who oversaw the U.S. Marines' initial operations in Afghanistan after the 9/11 attacks and served two tours in Iraq, said Russia miscalculated the resilience and capability of Ukrainian ground forces and the determination the Ukrainians would show in defending their territory. He said when he analyzed Russian forces arrayed along Ukraine's borders in February, before the invasion, he discounted the likelihood of a full-scale offensive.
"It seemed like the Kremlin attack plan might have been written in 2014. The Ukrainians have spent eight years building up their military and training," he said. Barranco credited training the Ukrainians have received since 2014 by U.S. National Guard units from California and other states in small-unit tactics for some of Ukraine's battlefield successes.
In the past 48 hours, Russian forces have struggled to maintain offensive actions northwest and east of Kyiv and have lost ground, with Ukrainian ground forces reoccupying territory they had lost, according to the General Staff of Ukraine's Armed Forces. Ukrainians say they have now managed to encircle the Russian-occupied towns of Bucha, Irpin and the village of Hostomel northwest of Kyiv.
Earlier this week, the Ukrainians retook the strategically located village of Makariv outside Kyiv. Much of the success rests with the Ukrainians targeting Russia's already challenged supply lines.
Britain's Defense Ministry said the Ukrainians will likely continue to target logistical assets in Russian-held areas, forcing the Russians to "prioritise the defence of their supply chain and deprive them of much needed resupply."
British defense officials also confirmed Friday that Ukraine has reoccupied towns east of Kyiv. "Ukrainian counter-attacks, and Russian Forces falling back on overextended supply lines, has allowed Ukraine to re-occupy towns and defensive positions up to 35 kilometers east of Kyiv," they said in a public intelligence update.
"In the south of Ukraine, Russian Forces are still attempting to circumvent Mykolaiv as they look to drive west toward Odesa, with their progress being slowed by logistic issues and Ukrainian resistance," they added.
Russian forces also appear to be preparing defensive positions around Kyiv, ready for a war of attrition. Earlier this week VOA reported that satellite imagery released by Maxar Technologies, a space technology and earth-observation company, appeared to show Russians soldiers building protective dirt berms near the villages of Ozera, Zdvyzhivka and Berestyanka, northwest of Kyiv, and around Antonov Air Base.
The berms are likely being built to guard against Ukrainian counterattacks, Western officials said.
"The Ukrainians know their territory — they know their ground. They've thought about this for a long time, and they are outperforming the Russians at the small-unit level," Barranco told VOA.
He and other military analysts said the Ukrainians are using a variety of tactics to push the Russian forces onto the back foot.
Among them are setting up so-called kill boxes, or defined target areas, and then drawing their foes into them; unleashing highly focused and ferocious attacks on isolated Russian troops; creating fallback routes after ambushes as they set up a subsequent attack; and striking mechanized units when they are stalled.
Another advantage the Ukrainians are exploiting is competent leadership by noncommissioned officers (NCOs), the officials say, which is also consistent with U.S. military doctrine and training.
"The U.S. puts a lot of focus on building a professional, noncommissioned officer corps of corporals and sergeants who understand the big picture and are given the delegated authority to make decisions on the battlefield as they lead their units," Barranco said.
"Junior officers are also taught to work closely with professional NCOs. The Russian military has acknowledged they have a problem with poorly trained NCOs and have started an NCO academy because they realize they do not have good leadership at the lower levels," he added.