Abu Ibrahim 'Abdullah bin Abu Aufa (May Allah be pleased with them) reported:
We were with the Messenger of Allah ﷺ on a journey and he was observing Saum (fasting). When the sun set, he ﷺ said to a person, "Dismount and prepare the ground roasted barley drink for us." Upon this he replied, "O Messenger of Allah, there is daylight still." The Messenger of Allah ﷺ said, "Get down and prepare barley drink for us." He said, "But it is still daytime." The Messenger of Allah ﷺ again said to him, "Get down and prepare barely drink for us." So he got down and prepared a barley liquid meal for him. The Prophet ﷺ drank that and then said, "When you perceive the night approaching from that side, a person observing Saum (fasting) should break the fast." And he ﷺ pointed towards the east with his hand.

[Al-Bukhari and Muslim].

وعن أبي إبراهيم عبد الله بن أبي أوفى، رضي الله عنهما قال: سرنا مع رسول الله ﷺ وهو صائم فلما غربت الشمس قال لبعض القوم: "يا فلان انزل فاجدح لنا، فقال: يا رسول الله لو أمسيت؟ قال: "انزل فاجدح لنا" قال: إن عليك نهارًا، قال: "انزل فاجدح لنا" قال: فنزل فجدح لهم فشرب رسول الله ﷺ ثم قال: "إذا رأيتم الليل قد أقبل من ههنا، فقد أفطر الصائم" وأشار بيده قبل المشرق. ((متفق عليه))