Valmiki Ramayana Yuddha Kanda Sarga 106 Shloka 21

तव your, विश्रामहेतोः reason is to give rest, तथा in that way, एषाम् all these, रथवाजिनाम् horses of the chariot, रौद्रम् terrific feat, खेदम् fatigue, वर्जयता to relieve, मया by me, इदम् in this way, क्षमम् deserve to be excused, कृतम् for the action

"The reason for retreating in this way is to give you rest and relieve the horses from the terrible feat and fatigue. I deserve to be excused for this action."