British defence minister Ben Wallace said on Thursday NATO would keep bolstering its eastern flank to counter Russian threats, and repeated accusations the Kremlin was building up forces around Ukraine. “We are deadly serious in how we’re going to face the threat that is currently being posed to both Ukraine and potentially to our security,” Wallace said. He was speaking ahead of talks in Brussels between NATO defence ministers and their counterparts from Ukraine and Georgia. “This is not a joke or a light matter. This is a real challenge to the stability of Europe,” Wallace added. “One of the…