Russia will remain an imminent threat to Nato even if there is eventual peace in Ukraine, and the western alliance needs to increase its air and missile defences, its secretary general, Mark Rutte, warned in a speech at the Chatham House thinktank in London. 'Let’s not kid ourselves, we are all on the eastern flank. There is no east or west, there is just Nato,' he said, adding that for Russian missiles 'the distance between European capitals is only a few minutes'.