All of this begs the question: in the end, was the Kursk offensive worth it? Actually, people have posed that question from the very beginning. When Kiev was deliberating over the invasion, some generals doubted the benefits would be worth the cost.

Ukrainian forces are under intense pressure in Russia's Kursk region, where they grabbed a chunk of land last August and have held on to it through more than seven months of fierce fighting.

Russia's Security Council's Deputy Chairman Dmitry Medvedev attends a meeting of the Council for Science and Education at the Joint Institute for Nuclear Research in the Moscow region's city of Dubna,