Russia will likely surpass 1 million casualties in its war on Ukraine this summer, according to one of the world’s leading think tanks.

With high casualty figures and the slow pace of Russia’s territorial gains, President Vladimir V. Putin could face years more of a grinding war of attrition in Ukraine.

Russia’s ongoing war on Ukraine has led to around 1.4 million troop casualties on both the sides, according to a study by Center for Strategic and International Studies (CSIS). While Russia has suffered 1 million casualties,