Mishkat al-Masabih 3 Purification كتاب الطهارة 45

وَعَن ابْن عُمَرَ أَنَّ عُمَرَ بْنَ الْخَطَّابِ رَضِيَ اللَّهُ عَنْهُ قَالَ: إِن الْقبْلَة من اللَّمْس فتوضؤوا مِنْهَا

Ibn ‘Umar reported ‘Umar b. al-Khattab as saying, “A kiss is connected with sexual intercourse, so perform ablution on that account.”