Ukrainian officials have announced that they are planning an offensive against Russian-backed separatists in the Donbas region, a move that could further escalate tensions between Russia and Ukraine. However, tensions may not be the only obstacle to Ukraine's victory, as Western intelligence sources have raised concerns about Ukraine's military preparedness. The US, in particular, has denied Ukraine's request for F-16s, and the lack of long-range artillery puts Ukraine at a major disadvantage in the upcoming offensive. Ukrainian officials have also stated that they are currently "losing in the sky" due to Russia's air supremacy in the region. While Ukraine has received the Patriot missile-defense system recently, the country is still lacking in air defenses and long-range strike capabilities. Experts noted that Russia's strategy appears to be to exhaust Ukraine's air defenses before unleashing a barrage of Russian missiles. The question is whether the Ukrainian military's current capabilities will be sufficient to mount a successful counteroffensive without the aid of US F-16s and long-range artillery.