SummaryGermany’s government has authorised the supply of about 50 anti-aircraft tanks to Ukraine, in a major policy shiftBerlin's decision comes as the US and its allies meet at an airbase in Germany to pledge more weapons for UkraineSpeaking after meeting the UN's secretary general in Moscow, Vladimir Putin repeats his justifications for invading Ukraine but says he has hopes for a diplomatic solutionHe says there is no more fighting taking place in the southern Ukrainian city of Mariupol, which has seen intense bombardment by RussiaEarlier Russian Foreign Minister Sergei Lavrov warned Nato against supplying military aid to Ukraine, saying there was a risk of the conflict escalating into World War ThreeUN Secretary General Antonio Guterres described discussions with Lavrov as "frank", but insisted he was visiting Moscow as a "messenger of peace"