"Sanction" has to be an autoantonym. To explicitly allow something is to implicitly forbid whatever is not that something, and to explicitly forbid something to implicitly allow whatever is not that something. Or, at minimum, the not that something in both cases exists in some ternary in-between state.

Thus, any word that exists in this vein is going to end up meaning what is forbidden and what is allowed.

One can sanction a country by only allowing it to trade oil, or one can sanction a country by forbidding it from trading food, clothes, and manufactured goods.