European Union countries possessing Patriot air defense systems appeared hesitant on Monday to give any to Ukraine, which is desperately seeking at least seven of the missile batteries to help fend off Russian air attacks.

Russia’s air force is vastly more powerful than Ukraine’s, but sophisticated missile systems provided by Kyiv’s Western partners can pose a major threat to Russian aviation as the Kremlin’s forces slowly push forward along the roughly 1,000-kilometer (620-mile) front line in the war, AP reported. 

Dutch Foreign Minister Hanke Bruins Slot said the Netherlands is “looking at every kind of possibility at the moment” and is offering financial support to a German initiative to help Ukraine bolster its air defenses and buy more drones.

Asked at a meeting of EU foreign and defense ministers why the Netherlands is reluctant to send some of its Patriot systems, Slot said: “We are looking again if we can deplete our store of what we still have, but that will be difficult.”