What is the ruling on investing in foreign banks through non-Islamic funds?

Contributing to a usurious bank is not permissible, due to the cooperation in sin and aggression it entails. Allah Almighty has said: "And cooperate in righteousness and piety, but do not cooperate in sin and aggression." Furthermore, the one who consumes usury and the one who feeds it are equal in sin, as the Prophet, peace and blessings be upon him, said: "Allah has cursed the one who consumes usury, the one who feeds it, and its two witnesses," and he said: "They are equal."