Imam al-Nawawi says, “It is disliked for one to kiss his spouse if it results in sexual arousal and not disliked otherwise, and there is no difference between the young and the old in this matter. The possibility of sexual arousal and discharging semen is what is to be considered. If a young or old man is moved sexually by kissing his spouse, then it is disliked; it is not disliked otherwise. Thus, it is more cautious to abstain from the act to avoid the possibility of arousal and semen discharge.”
A’isha (ra) reported that, “The Prophet (pbuh) kissed and embraced (his wives) while fasting.”
The take away message here is that kissing one’s spouse with the intention of fulfilling a desire is disliked according to the majority of Muslim jurists, as it could lead to the invalidation of one’s fast. Kissing becomes haram/impermissible if it leads to ejaculation of mani, as that invalidates the fast.