Is ejaculation due to foreplay with one's wife during the daytime in Ramadan considered a sin that necessitates expiation?

You committed a sin by breaking your fast and violating the sanctity of Ramadan (definition) through foreplay with your wife until ejaculation. You must abstain from food and drink for the rest of the day and make up that day later. Your regret is considered repentance, as the Prophet (peace be upon him) said: "Regret is repentance." If you ejaculated without intercourse, you are not required to offer expiation (kaffarah (definition)), but only to make up the day. However, if intercourse occurred, you must offer the severe expiation (kaffarah mughalladhah): freeing a slave, or fasting for two consecutive months, or feeding sixty needy people. This ruling applies to both you and your wife; if she also ejaculated, her fast is invalidated, and she must repent and make up the day.