German Chancellor Olaf Scholz on Tuesday urged allies to dig deeper in their military stocks to help Ukraine bolster its air defence against Russian attacks.

"I would like to make a heartfelt plea to everyone here today: please support our initiative to strengthen Ukraine's air defence with everything that is possible," Scholz told delegates gathered in Berlin for the Ukraine Recovery Conference.

Germany is leading an effort called Immediate Action on Air Defence for Ukraine, and has itself contributed three Patriot systems to Kyiv.