Jens Stoltenberg, the Nato secretary general, has said that Ukraine is getting “closer and closer” to membership. He added, however, that it is too early to say when it may happen, due to the need for consensus of all allies. Member states are meeting in Washington DC this week to mark the 75th anniversary of the world’s biggest security organisation as Russia presses its advantage on the battlefield in Ukraine. The three-day summit will focus on ways to reassure Ukraine of Nato’s enduring support and offer some hope to its war-weary citizens that their country might survive the biggest land conflict in Europe in decades.