MI5 spy chief says Russia, China and Iran top the threat list to U.K.Britain faces major security threats from the trio of Russia, China and Iran, which all use coercion, intimidation and even violence on foreign soil to pursue their interests, the U.K.’s domestic intelligence chief said Wednesday.Last week, the U.K. government summoned Tehran’s top diplomat in London for a dressing-down, accusing the Islamic Republic of threatening journalists working in Britain.U.K-based Farsi-language satellite news channel Iran International said British police had warned two of its journalists about “an imminent, credible and significant risk to their lives and those of their families.”In a speech outlining the major threats to the U.K. from hostile states and terror groups, McCallum said there is a risk Russia, China and Iran could help one another, “amplifying their strengths.”Iran’s Foreign Ministry says it has summoned Britain’s ambassador to protest what it called a hostile atmosphere created by London-based media outlets.McCallum cast China as an even longer-term problem, saying “the activities of the Chinese Communist Party pose the most game-changing strategic challenge to the U.K.”The CIA says it will create a top-level working group on China as part of a broad U.S. government effort focused on countering Beijing’s influenceUsing a sports analogy, McCallum said, “Russia thinks nothing of throwing an elbow in the face and routinely cheats to get its way.”“The Chinese authorities present a different order of challenge,” he said.He said such activities were likely to grow as Chinese President Xi Jinping “consolidates power on an indefinite basis.”China’s paramount leader, Xi Jinping, sees himself as a savior, anointed to steer the Communist Party and China away from corruption and foreign influence, into a ‘new era’ of prosperity, power and political devotion."