The client has an online businesses on Amazon in which he purchased items from overseas → store them in Amazon warehouses in US → then sell the items through their platform (mostly in US and Canada). So items arrived in US got taxed and when he sold his items in US, Amazon also withheld taxes which I guess is for the sales tax because it varies based on the state the items were shipped to.
My question is: Could I claim these taxes as expense for his Canadian T2 ( I would most likely put it under business taxes - Gifi code 8762 )