The federal government announced this week at a meeting of provincial premiers that it plans to impose a 10-percent federal tax on sales of recreational cannabis. According to the government and media sources, the tax would be set at $1 per gram on purchases under $10 and 10 percent on amounts above $10, with revenue split 50-50 between the federal government and the provinces. 

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Globe and Mail: Trudeau's plan for marijuana tax catches premiers off guard