Abu Zayd (may Allah have mercy on him), the freed slave of Tha'labah, narrates from Sayyiduna Ma'qil bin Abi Ma'qil al-Asadi (may Allah be pleased with him) - who was one of the Companions of the Messenger of Allah (peace and blessings be upon him) - that the Messenger of Allah (peace and blessings be upon him) forbade facing the two qiblahs (that is, the House of Allah and Bayt al-Maqdis) while relieving oneself or urinating.
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17683