KYIV -- Moscow's forces, bolstered by North Korean troops, have intensified their offensive against Ukrainian troops in Russia’s Kursk region, as Kyiv's outnumbered soldiers attempted to resist the onslaught there and elsewhere on December 17.
"For the third day, the enemy has been conducting intensive offensive operations on the territory of the Kursk region, actively using units of the North Korean Army," said General Oleksandr Syrskiy, Ukraine's top military commander, in an address broadcast online.
Pyongyang’s decision to send troops to Russia appears to have come at a high cost so far.
Ukrainian and U.S. officials on December 16 said North Korean troops have been fighting alongside Russian forces in Kursk and that some have been killed or injured.
On December 17, a senior U.S. military official, speaking on the condition of anonymity, told news agencies that North Korean forces have suffered "several hundred" casualties in the Kursk fighting -- from lower-level troops to those "very near to the top."
"These are not battle-hardened troops. They haven't been in combat before," the official added.
SEE ALSO: Russian General Charged With Chemical Weapons Use In Ukraine Killed In Blast Claimed By KyivRFE/RL has not been able to independently verify the claims. Russia has not commented on the reports.
Syrskiy said the situation all along the front line "remains difficult" after Russian troops had seized "the strategic initiative" in recent weeks.
He said Russian forces were continuing their drive to capture the strategic Donetsk city of Pokrovsk, which appears to be mostly deserted by civilians.
Local military commanders in the region said defense forces were "holding back the onslaught," although the overall situation in the Donetsk city -- with a prewar population of about 65,000 -- appeared perilous, according to many Ukrainian officials.
Over recent months, Russia has pressed its manpower advantage to push back against Ukraine's shock incursion into its Kursk region in August and to gain territory in eastern Ukraine, prompting Ukrainian officials to increase pleas to Western partners for additional military aid.
Elsewhere, Ukraine's SBU security service said it had uncovered a "large-scale network" of agents working for Russian military intelligence that had attempted to collect information on Ukraine's supply of Western-supplied F-16 warplanes, which are based at secret sites throughout the country.
SEE ALSO: Russian General Charged With Chemical Weapons Use In Ukraine Killed In Blast Claimed By Kyiv"As a result of the special operation, 12 Russian agents and their informants were exposed. Some of them are deserters who voluntarily left the units of the armed forces of Ukraine, and when they were hiding from justice, they were recruited by the Russian special service," the security office said.
On the political front, Polish Prime Minister Donald Tusk met with Ukrainian President Volodymyr Zelenskiy in Lviv, vowing his support for Ukraine's NATO membership hopes, while Zelenskiy urged Western allies to "urgently strengthen Ukraine" with additional aid.
On December 16, U.S. President-elect Donald Trump told a news conference that Zelenskiy and Russia's Vladimir Putin must be prepared to "make a deal" to end the "horrible" war in Ukraine.
SEE ALSO: What A Ukraine Peace Plan Could Look Like"He should be prepared to make a deal, that’s all," Trump said of Zelenskiy during a news conference at his Mar-a-Lago club in Florida.
Putin must also "make a deal," Trump then added.
"Got to be a deal. Too many people being killed," he said.
Trump, who takes office on January 20, said he would speak with Zelenskiy and Putin on ways to end the war, but he did not answer directly when asked if Ukraine would be forced to cede territory to Russia.
President Joe Biden's administration has attempted to speed deliveries of aid to Kyiv ahead of the return to the White House of Trump, who has criticized the amount of assistance Biden has provided to Ukraine since Russia launched its full-scale invasion in February 2022.
SEE ALSO: Ukraine Live Briefing: Talking About Peace TalksMeanwhile, in Tallinn, Estonia, leaders of the 10-nation Joint Expeditionary Force (JEF) on December 17 vowed continued support for Ukraine.
"We reiterate that Ukraine’s victory is vital to all our security and the preservation of rules-based international order," a joint statement read.
"We call on all third countries, including [North Korea], Belarus, Iran, and China, which are directly or indirectly enabling Russia’s aggression, to cease offering the support Moscow requires to prolong the war and the suffering of the Ukrainian people."
The statement is signed by Denmark, Estonia, Finland, Iceland, Latvia, Lithuania, the Netherlands, Norway, Sweden, and the United Kingdom.