All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
It is forbidden for the fasting man to have sex or take part in foreplay during the daytime with his wife in Ramadan. The Prophet Muhammad, sallallaahu ‘alayhi wa sallam said: “One gives up one's food, one's drink and one's desire for Allaah's sake (when fasting).” [Al-Bukhari and Muslim] It is, however, permissible for him to kiss his wife if he can control himself and does not come to a point where he then has intercourse or ejaculates – in which case it is forbidden for him to do so. The evidence for this is the Hadeeth of the Prophet, sallallaahu ‘alayhi wa sallam, where ‘Aa’ishah reported that, “Allaah's Messenger, sallallaahu ‘alayhi wa sallam, would kiss (his wives) while fasting and embrace (them) while fasting, but he had the greatest mastery over his desire.” [Al-Bukhari and Muslim] Imaam An-Nawawi said: “There is no disagreement that kissing does not nullify the fasting, unless one ejaculates.”
Allaah Knows best.