Ukrainian forces suffered around 400 casualties, and 16 military vehicles were put out of service in the Donetsk region in the past 24 hours, the Russian Ministry of Defence announced on Saturday.

"In the Donetsk direction ... Enemy casualties over the past 24 hours amounted to 400 Ukrainian servicemen killed and wounded, 14 armored combat vehicles, two vehicles, and a D-20 howitzer," the ministry stated.

Furthermore, Russian forces thwarted five Ukrainian offensives in the region, as also repelled four attacks in the Kupyansk region and another in South Donetsk.

In Kupyansk, Ukraine lost over 130 soldiers while another 40 were eliminated near the village of Krasnyi Lyman as the Ukrainian armed forces suffered 190 casualties in Zaporozhye.

On Saturday morning, a Ukrainian drone carried out an attack on the Novgorod military air base in Russia, as damages were constricted to one warplane while no casualties were reported, the Russian ministry revealed.

"Today, at about 10:00 Moscow time [07:00 GMT], the Kiev regime carried out a terrorist attack using a copter-type UAV [unmanned aerial vehicle] against a military airfield in the Novgorod Region," Russia's Ministry of Defense explained.

A fire broke out in the aircraft parking space as a result of the attack and was promptly extinguished by security services. The ministry also said that the drone was spotted by personnel at the external observation post of the airfield, as security forces tried to bring it down using firearms.

"As a result of the terrorist attack on the territory of the airfield, a fire broke out at the aircraft parking space, which was promptly extinguished by fire brigades. One warplane was damaged, there were no casualties as a result of the terrorist attack," the ministry added.

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US greenlights F-16s to Ukraine

In the context of the failed Ukrainian counteroffensive, the US State Department announced on Friday that it would allow the Netherlands and Denmark to supply Ukraine with F-16 fighter jets but only once the country's pilots are trained to operate them, as both European nations are leading the training programs. 

"This way, Ukraine can take full advantage of its new capabilities as soon as the first set of pilots complete their training," a State Department spokesperson said.  

It remains unclear how long it will be before the first set of Ukrainian pilots are completely ready to fly the jets, with officials hoping for pilots to be ready by 2024 while training by an 11-nation coalition is due to start this month. 

Ukrainian Minister of Defense Oleksii Reznikov praised the "great news from our friends in the United States" alongside Netherlands Defense Minister Kajsa Ollongren who posted on social media that "It allows us to follow through on the training of Ukrainian pilots". She did acknowledge however that "everything takes time", as reported by the ANP new agency. 

Even further before then, back in May, Ukraine's Yuri Sak, an advisor to the Ukrainian defense minister, expressed hopes to receive the first batch of F-16s in September or October of this year. That, however, is highly unlikely to happen, given that training is not over yet and language is seeming to be an impediment. In addition, the counteroffensive does not seem to be working much in Ukraine's favor. 

Read more: US allows Denmark, Netherlands to send F-16s to Ukraine post-training