BERLIN, Oct 1 (Reuters) - Germany will deliver the first of four advanced IRIS-T air defence systems to Ukraine in the coming days to help ward off drone attacks, its defence minister Christine Lambrecht said during an unannounced visit to Odessa on Saturday.Register now for FREE unlimited access to Reuters.comUkraine has been seeing more attacks from Iranian-made kamikaze drones in recent weeks, costing lives and causing serious damage to infrastructure.Earlier, meeting her Moldovan counterpart Anatolie Nosatii in Chisinau, she urged Western countries not to be deterred from arming Ukraine by threats that Russia could use nuclear weapons.Germany is facing calls to step up its support for Ukraine, including by sending offensive weapons such as the modern tanks Kyiv says it needs to take the fight to Russian forces.Berlin has so far resisted such calls, arguing that such moves would escalate the situation and pointing out that no other country has so far sent tanks more modern than old Soviet stock sent by former Warsaw Pact countries."