Maliks Muwatta Book 18, Hadith Number 18.

Section : Restraint in Kissing when Fasting.

Yahya related to me from Malik that he had heard that A’isha, the wife of the Prophet, may Allah bless him and grant him peace, would say, when she mentioned that the Messenger of Allah, used to kiss while fasting, “And who among you is more able to control himself than the Messenger of Allah, may Allah bless him and grant him peace?”

Yahya said that Malik said that Hisham ibn Urwa ibn az-Zubayr had said, “I do not think that kissing invites to good for people who are fasting.”