Narrated Ibn 'Abbas: The Prophet (ﷺ) left Medina for Mecca till he reached 'Usfan, He then called for a vessel (of water). It was raised to his mouth to show it to the people, and that was in Ramadan. Ibn 'Abbas used to say: The Prophet (ﷺ) fasted and he broke his fast. He who likes may fast and he who likes may break.
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ مَنْصُورٍ، عَنْ مُجَاهِدٍ، عَنْ طَاوُسٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ خَرَجَ النَّبِيُّ صلى الله عليه وسلم مِنَ الْمَدِينَةِ إِلَى مَكَّةَ حَتَّى بَلَغَ عُسْفَانَ ثُمَّ دَعَا بِإِنَاءٍ فَرَفَعَهُ إِلَى فِيهِ لِيُرِيَهُ النَّاسَ وَذَلِكَ فِي رَمَضَانَ . فَكَانَ ابْنُ عَبَّاسٍ يَقُولُ قَدْ صَامَ النَّبِيُّ صلى الله عليه وسلم وَأَفْطَرَ فَمَنْ شَاءَ صَامَ وَمَنْ شَاءَ أَفْطَرَ .
sunnah.com