A peace deal between Russia and Ukraine will fail unless it is backed up by “robust” security guarantees from western powers, the UK prime minister has said. Keir Starmer, speaking ahead of talks with European leaders in Berlin, told MPs on Monday he was opposed to any agreement that did not include sufficient military guarantees for Ukraine, as Kyiv comes under mounting US pressure to sign up to a Trump-backed plan. Starmer said: “European history is full of peace agreements that failed and sometimes led to even greater conflict. And that is why it’s really important we attend to this...