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Canadian Prime Minister Justin Trudeau and Saudi Arabia's Crown Prince Mohammed Bin Salman.
A dispute between Canada and Saudi Arabia that started with a tweet has escalated to an all-out slanging match that has all but severed relations between the two countries entirely.
Saudi Arabia has cancelled flights to Canada, recalled students studying there, cut investment and issued lurid threats.
Meanwhile Canada has pledged to hold its ground, leaving the temperature nowhere to go but up.
Scroll down for a full timeline explaining how the dispute has snowballed into a full-blown crisis.