Ukrainian soldiers of the 1st Separate Assault Battalion Da Vinci at a training exercise in the Dnipropetrovsk region -AFP

Five months after a surprise offensive into Russia, Ukrainian troops face mounting losses in the Kursk region. Intense fighting has left many demoralized. Some want to hold at all costs while others question the value of having gone in at all. Battles are so intense that some Ukrainian commanders can't evacuate the dead.

Communication lags and poorly timed tactics have cost lives, and troops have little by way to counter-attack, seven front-line soldiers and commanders told The Associated Press.

Since being caught unaware by the lightning Ukrainian incursion, Russia has amassed more than 50,000 troops in the region, including some from North Korea. Moscow's counter-attack has killed and wounded thousands and the overstretched Ukrainians have lost more than 40% of the 984 sq km of Kursk they seized in August.

Ukrainian President Volodymyr Zelenskyy had  hoped controlling Kursk would help force Moscow to negotiate an end to the war. But five Ukrainian and Western officials in Kyiv, who spoke on condition of anonymity, said they fear gambling on Kursk will weaken the whole 1, 000-kilometer (621-mile) front line, and Ukraine is losing precious ground in the east.

"We have, as they say, hit a hornet's nest. We have stirred up another hot spot," said Stepan Lutsiv, a major in the 95th Airborne Assault Brigade.

Army chief Oleksandr Syrskyi has said that Ukraine launched the operation because officials thought Russia was about to launch a new attack on northeast Ukraine. It began on August 5 with an order to leave Ukraine's Sumy region for what they thought would be a nine-day raid to stun the enemy.