Ukraine is finalizing preparations for its anticipated spring counteroffensive against Russia, and President Volodymyr Zelenskyy says his country will fight with or without Western military jets.

Ukraine’s battlefield progress depends heavily on military supplies from the West. Military experts say, without advanced jets from Kyiv’s NATO allies, the counteroffensive will likely consist of costly battles of attrition.

In recent days, NATO Secretary-General Jens Stoltenberg was among Western leaders who held meetings with Ukraine’s leadership and military command. He emphasized that through the Contact Group led by the United States, NATO allies and partners have provided more than 98% of the combat vehicles promised to Ukraine, including over 1,550 armored vehicles, 230 tanks and vast amounts of ammunition.

“In total, we have trained and equipped more than nine new Ukrainian armored brigades. This will put Ukraine in a strong position to continue to retake occupied territory,” said the NATO secretary general last week during a press conference.

Ukraine says it needs more. Ukraine’s top military commander, General Valerii Zaluzhnyi, recently held a working meeting with U.S. Army General Christopher Cavoli. According to VOA sources, the generals conferred on Ukraine’s military abilities and agreed on the need for a thorough assessment of Ukraine’s readiness for a counteroffensive.

Posting on Facebook after the meeting, Zaluzhnyi wrote that participants had “considered in greater depth the operational situation along the entire front line … the likely scenarios, threats and prerequisites for our future actions.”

Zaluzhnyi added, “We focused on the importance of timely supply of sufficient ammunition and materiel. I emphasized the need to provide Ukraine with a wide range of armament and air defense systems, which will significantly help us to solve the problematic issues in our resistance to Russian aggression.”

VOA sources in Ukraine’s military command confirmed that Ukraine has largely spent its supply of aged Soviet military hardware and munitions. Ukraine’s military has been fighting on the eastern and southern fronts in recent months, hoping to exhaust Russian forces without giving up territory.

Ukraine is having success in that regard, according to U.S. National Security Council spokesperson John Kirby.

“Russia has exhausted its military stockpiles and its armed forces and since December alone,” Kirby told reporters Monday. “[J]ust since December, we estimate that Russia has suffered more than 100,000 casualties, including over 20,000 killed in action, nearly half of whom were Wagner [Group] soldiers.”

At the same time, Ukraine is transitioning to Western weapons systems, making the country even more reliant on Western military support.

As it preps for a spring counteroffensive, one of Ukraine’s critical unmet needs is fighter jets, according to Gustav Gressel, a senior fellow at the European Council on Foreign Relations.

In a recent article, Gressel wrote that “[e]xtensive fortifications in the Russian rear may slow Ukrainian advances long enough to allow Russian aircraft to strike the forces clearing obstacles. …To screen the ground forces from such attacks, the Ukrainian air force will have to come out, at least to disrupt Russian attacks.”

Addressing Ukraine’s need for jets, Gressel wrote: “The US should learn from last year’s delay over tank deliveries and approve their release as soon as possible.”

“The end of the war depends on Ukraine,” NATO’s assistant secretary-general for public diplomacy, Ambassador Baiba Braže, recently told VOA. “[T]he most important part is ensuring that Ukraine is supported in maximum ways. If it wants to continue fighting, it has the capability to continue fighting.”