Does the imam need a sutrah if there is a meter and a half between him and the wall?

Question:
The Honorable Shaykh, may Allah grant you success, says: The imam of a mosque who prays with the people has about a meter and a half between him and the wall of the mihrab. He says: The imam of a mosque prays with the people, and there is about a meter and a half between him and the wall of the mihrab. Is he required to find a sutrah for this space of a meter and a half?

Answer:
Determine that there be three cubits between him and the wall, three cubits. I do not know what that equals in meters. If the distance between him and the wall is three cubits, there is no harm in that; the wall serves as his sutrah. Yes.