Where provisional enforcement has been ordered, it may be stopped, in the event of an appeal, only by the first president and in the following cases:
1° If it is prohibited by law;
2° Where there are serious grounds for setting aside or reforming the decision and enforcement is likely to entail manifestly excessive consequences; in the latter case, the first president may also take the measures provided for in Articles 517 and 518 to 522.
The same power belongs, in the event of opposition, to the judge who handed down the decision where enforcement is likely to entail manifestly excessive consequences.