Rob Lee, a researcher at the War Studies department at King’s College London, said the 200th Motorized Infantry Brigade had been involved near Kharkiv, Ukraine’s second city, where it had suffered heavy casualties and lost a large amount of equipment. Regarding the repaired 200th Motorized Infantry Bridge, he said it now “has a mix of reservists, volunteers and servicemen from the military police, coast defense units and sailors from ships.” This patchy development reflects the compromises the Russian military must make to bolster its forces in the Donbass after more than four months of war that has killed at least 20,000 Russian soldiers and wounded many more. But on Thursday, an optimistic Mr Putin said the West should stop using Ukraine as a proxy and instead meet the Russian military on the battlefield. “Today we hear that they want to defeat us on the battlefield. What can you say, let them try,” he said. “Everyone should know that, generally speaking, we haven’t started anything in earnest yet.”