Sayyiduna Thawban (may Allah be pleased with him) narrates: The Messenger of Allah (peace and blessings be upon him) passed by a man who was being cupped in Ramadan while he was lending to a man, and he (peace and blessings be upon him) said: "The one who cups and the one who is cupped have both broken their fast."
Hadith Referenceالمعجم الكبير للطبراني / باب الثاء / 1404