Is working in the cigarette (tobacco) trade forbidden or permissible, and what is the ruling on working as an employee in a company that trades in it?

Smoking and trading in it are forbidden (haram). It is not permissible to work for tobacco companies, even if one does not directly engage in sales, because this constitutes cooperation in sin and aggression, which Allah has forbidden in His saying: "And do not cooperate in sin and aggression. And fear Allah; indeed, Allah is severe in penalty."