The following sentence was correct on an SC question but the pronoun "it" seemed to be too ambiguous to me. I see now that all of the preceding nouns other than code are plural, and therefore "it" could not refer to any of them, but if all of the nouns were singular would I be correct in that "it" is too ambiguous?

Because the new maritime code provides that even tiny islets can be the basis for claims to the fisheries and oil fields of large seas, it has already stimulated international disputes over uninhabited islands.