Zakat on Unlawful (Haram) Wealth?

Firstly we should know that Allah commands His believing servants to spend on charity. Ibn Abbas states that this should from the pure, honest money they have earned and from the fruits and vegetables that have been grown for them in the land. Ibn Abbas said: “Allah commanded them to spend from the purest, finest and best types of money, and prohibited them spending from evil and dishonest money because Allah is pure and good and only accepts that which is pure and good.” [Ibn Kathir: 1/630]