Sir Keir Starmer has warned Vladimir Putin he will face “severe consequences” if he breaches any ceasefire deal.The UK prime minister issued the warning in response to a question about whether UK troops could be drawn into Russia’s war in Ukraine as he attended a meeting of defence chiefs from 31 allied countries aimed at drawing up military plans to enforce a peace deal.

Senior military officers from countries across Europe and beyond are meeting outside London to flesh out plans for an international peacekeeping force for Ukraine as details of a partial ceasefire are worked out.