Is it permissible for a pilgrim in a state of Ihram to cut his nails before slaughtering the sacrificial animal (hady)?

If he does that before assuming ihram, there is no harm, unless he intends to offer a sacrifice and the month of Dhul-Hijjah has begun, in which case it is not permissible. As for after assuming ihram, it is not permissible, because a person in ihram is not allowed to clip his nails or remove any of his hair, unless he has completed his circumambulation (tawaf) and striving (sa'i) for Umrah, or thrown the Jamrat al-Aqabah in Hajj, whereupon he becomes permissible by shaving or shortening his hair.