Musnad Ahmad 1156:220

'Abd al-Malik ibn 'Amr narrated to us, Musa ibn 'Ali narrated to us, from his father, from Abu Qays, the freed slave of 'Amr ibn al-'As, who said: I said to Umm Salamah: "Did the Messenger of Allah (peace and blessings of Allah be upon him) kiss while he was fasting?" She said: "No." I said: "But 'Aishah informs the people that the Messenger of Allah (peace and blessings of Allah be upon him) used to kiss while he was fasting." She said: "I said: Perhaps he could not restrain himself from her out of love, but as for me, I do not."