Please use the sharing tools found via the share button at the top or side of articles. Copying articles to share with others is a breach of FT.com T&Cs and Copyright Policy. Email firstname.lastname@example.org to buy additional rights. Subscribers may share up to 10 or 20 articles per month using the gift article service. More information can be found here.https://www.ft.com/content/4ad0fddd-eba6-4b8a-86d2-df847919969aPresident Volodymyr Zelenskyy this week recommitted his forces to defending the eastern city of Bakhmut just as western officials and even some Ukrainian soldiers suggested it might be wiser to pull back. The battle for Bakhmut, raging for nine months, has become an attritional trap, with Russians and Ukrainians trying to deplete each other’s ranks and gain an advantage for offensives later this spring. Kyiv claims to have killed thousands of Russian fighters, mainly mercenaries recruited from prisons and ordered to assault Ukrainian positions in human waves reminiscent of the first world war. But Ukraine is taking heavy losses too, potentially changing the cost-benefit assessment of holding on to the city. Russian attackers have gradually closed in on Bakhmut from the north, south and east, leaving only a narrow supply route in from the west for Ukraine’s troops. “The enemy is attacking from all sides,” a Ukrainian soldier told the Financial Times from Bakhmut. “We are getting supplies. But the situation is with each day getting more and more difficult.” US defence secretary Lloyd Austin this week said a Ukrainian retreat from the city would not be an “operational or strategic setback” and the head of Nato Jens Stoltenberg said it would it not be a “turning point”, comments that intimate they may both favour a withdrawal. But Zelenskyy has raised the stakes, ordering his armed forces to reinforce their positions there and warning that abandoning Bakhmut would leave the Russians an “open road” to the rest of Donetsk province, which Moscow is determined to seize. Zelenskyy this week justified his stance by claiming Russia was suffering much heavier casualties than Ukraine in its attempt to capture what his army calls “Fortress Bakhmut”. “We are destroying the occupier everywhere — wherever it yields results for Ukraine . . . Bakhmut has yielded and is yielding one of the greatest results during this war,” he said. Ukraine appears to be using the same tactics it deployed last summer during Russia’s assault on Severodonetsk and Lysychansk, the last two sizeable towns under Kyiv’s control in Luhansk province. The Ukrainian army eventually pulled out but only after inflicting heavy losses on Russian troops and militia drawn from occupied territories. Kyiv then took advantage of Russia’s depleted and overstretched forces by launching a lightning offensive to retake territory in north-eastern Ukraine and to liberate the city of Kherson in the south. The question, say western officials and experts, is whether Ukrainian losses in men and materiel might hinder its own capacity for a counter-offensive. At the very least, the losses might argue in favour of withdrawal to a new defensive line. Michael Kofman, director of the Russia studies programme at CNA, a think-tank, who visited Bakhmut earlier this week, said the argument about Ukraine’s diminished counter-offensive capacity “may be overstated”. “I think the main question is to what extent does defence of Bakhmut represent a strategy with diminishing returns relative to other options.” Assessing casualties on either side is a challenge for analysts and officials, all the more so those in the vicious fighting for Bakhmut. US and European officials estimate 200,000 Russian troops have been killed or seriously injured since February last year, and Ukraine about half that. One western official said Russia had suffered “between 20,000 and 30,000 casualties over the past six months”, adding that most of them were mercenaries fighting for the Wagner private military company. Wagner’s operations have been largely focused on Bakhmut. Nato officials estimate one Ukrainian had been killed or injured for every five Russians. Ukrainian national security chief Oleksiy Danilov last week estimated the ratio was “one to seven in our favour”. Either way, it implies Ukraine could have suffered several thousand casualties defending the city although its superior medical care means proportionately fewer Ukrainians die on the battlefield. “Ukraine is losing people all along the front line but Bakhmut has given them a unique opportunity to kill lots of Russians too, given the [meat grinder] tactics the Russians use,” the western official said. Yuriy Lutsenko, a former politician now serving as a captain in a Ukrainian drone unit that was rotated out of Bakhmut a few days ago, said both sides have faced shortages of artillery ammunition. But Ukraine was better positioned to exploit the situation by reducing the size of Wagner’s forces from an estimated “45,000 to 7,000”, he said. “Defending from a fortress is the more effective way to hold the line before launching your own counteroffensive,” Lutsenko added. Some experts worry Ukraine may be expending high-quality troops and equipment to kill mere Russian prison recruits as “cannon fodder”. But analysts at the Institute for the Study of War said Wagner was now committing some its elite forces to Bakhmut and that Russian airborne forces had also joined the fight. Ukrainian officials have argued that pulling out of the city would not necessarily give their forces a fresh advantage. Mykola Bielieskov, an analyst at Ukraine’s National Institute for Strategic Studies, said it was “quite difficult to conclude confidently whether attrition of Russian troops is better done using the current approach or might have been better had we left Bakhmut and shortened the front line”.