President Volodymyr Zelensky urged United States counterpart Donald Trump to help Ukraine with air ‌defence systems and interceptors as Russia threatens new strikes, saying that ballistic missiles remain Moscow’s “last major advantage on the battlefield”.

In a letter to Trump and the US Congress, seen by Reuters, Zelensky said: “I ask for your help in protecting Ukraine’s skies from Russian missiles. We have ​already proposed that Ukraine is ready to purchase the number of Patriot systems and interceptor missiles we ​need.”

Ukraine’s only means to shoot down Russian ballistic missiles is US-made interceptors for the Patriot air ⁠defence system. Throughout four years of war, Kyiv has been short of interceptors, but the Iran war has threatened ​to make resources even more scarce.

Since Trump took office, Ukraine has been purchasing Patriot missiles through NATO’s Prioritised Ukraine Requirements ​List (PURL) initiative, financed by its European allies.

“But the current pace of deliveries through the PURL programme is no longer keeping up with the reality of the threat we face,” Zelensky said in his letter.

“For us, for a nation fighting for its survival, there is hardly anything ​more painful to see than Patriot batteries with no missiles loaded,” he added.

Zelensky says action needed

Speaking in his nightly ​video address, Zelensky noted it was rare for a foreign leader to address a letter simultaneously to the US president and Congress, “but ‌the ⁠current situation requires action, swift and effective action. It is important that America hears Ukraine”.

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Zelensky said ensuring Ukraine’s protection from Russian ballistic missiles was critical to negotiating peace.

“The sooner we can provide greater protection against ballistic missiles, the faster we can ensure that diplomacy works,” he said. “As long as Russia relies on missiles, its interest in diplomacy is not genuine. ​We must correct this and ​we can only correct ⁠it together, with America.”

The letter was first reported by Ukrainian media outlet The Kyiv Independent.

Russia used 30 ballistic missiles against Ukraine in its latest massive strike on Sunday, and only 11 ​of them were shot down, according to Ukraine’s air force.

Zelensky also said Moscow’s troops ​launched two nuclear-capable ⁠intermediate-range ballistic Oreshnik missiles for that strike.

“One struck the Kyiv region, while another, reportedly, fell in temporarily occupied territory in Ukraine’s Donetsk region.”

In the letter, the Ukrainian leader outlined Ukraine’s success in fending off Russia’s full-scale aggression, now well into its ⁠fifth year, ​and expressed gratitude for US support.