Global/International/Worldwide Tensions Flare: Diplomatic Standoff Erupts Between Nations
Diplomatic relations have deteriorated/are at a breaking point/are strained between several nations/a pair of key players/two major powerhouses, sparking concerns/fears/an atmosphere of uncertainty about the potential for escalation/conflict/war. The source/cause/origin of this crisis/impasse/dispute is a long-standing territorial disagreement/a re