Ukraine has "almost certainly" accelerated the construction of defensive fortifications along several areas of the front line, the U.K. Defense Ministry wrote in its March 10 report.
The measures include anti-tank obstacles and ditches, infantry trenches, minefields, and other fortified defensive positions.
Further fortifying the front line means that Russian forces can struggle to advance in those areas and achieve any significant tactical gains.
Any effort to push forward in more fortified areas would "highly likely be accompanied by high (Russian) losses," the ministry added.
Kyiv's stalled counteroffensive in 2023 ultimately didn't result in the desired territorial gains against Russian forces, compelling the Ukrainian military to take a more defensive approach in the latest stage of the full-scale war.
During a press conference in December 2023, President Volodymyr Zelensky replied to a question about fortifications posed by a Kyiv Independent journalist, saying that the most powerful defenses have been constructed in Ukraine's northeastern Kharkiv Oblast.
"When I see this there but not in other oblasts, I ask concrete questions of our military leaders in other sectors: Is it sufficient?... and why is it weaker there than in Kharkiv Oblast?" Zelensky said.
According to Zelensky, he asked the military to unify the level of fortifications in various sectors to reach the same standards.
Illia Yevlash, a spokesperson for Ukraine's Khortytsia Operational and Strategic Group, said on Feb. 26 that Kharkiv Oblast's city of Kupiansk, a crucial logistics juncture that was temporarily occupied by Russia in 2022, is coming under renewed pressure by Moscow's troops.
Ukrainian forces, in turn, have built a line of defense and "powerful fortifications" near the city, "skillfully using the features of the landscape," Yevlash said on national television.
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