Does the imam appoint a substitute if he remembers that he is not in a state of ritual purity during the prayer?

Question:
Honorable Shaykh, may Allah grant you success, a questioner says: If the imam remembers that he is not in a state of ritual purity during the prayer, does he appoint someone to complete the prayer with the congregation?

Answer:
No, this falls under praying without ritual purity, so what he performed of it is invalid. His substitute starts the prayer anew, or he tells the congregation to wait and goes to perform wudu, as the Messenger (peace and blessings be upon him) did when he led the prayer and remembered that he had entered the prayer without wudu. He turned to them (peace and blessings be upon him) and said, "Stay in your places," then he went and performed wudu, came back, and prayed with them (peace and blessings be upon him).