Al-Hasan reported from ‘Umar that he said: "The impotent husband should be given a one-year respite. If he manages to have intercourse with her, (that will be fine) or else they should be separated.”
شرح الحديث :
This tradition shows that a man who cannot have sexual intercourse with his wife should be given a one-year respite. If he can do it, then his marriage contract is confirmed. Otherwise, both spouses should be separated.