One theory is that Ukraine may be running out of armed drones and its small, outnumbered air force may be wary of being shot down by Russian air defence batteri

One theory is that Ukraine may be running out of armed drones and its small, outnumbered air force may be wary of being shot down by Russian air defence batteries. Ben Barry from the International Institute for Strategic Studies (IISS) suggests the Ukrainians may well be safeguarding what resources they do have in readiness to counter-attack when the Russians get closer to Kyiv