Sayyiduna Talq bin Ali (may Allah be pleased with him) reports from the Prophet (peace and blessings be upon him) that he forbade fasting a day ahead of Ramadan until one sees the new crescent or the count is completed; and then people are not to stop fasting until they see it (the new crescent) or the count is completed.
Al-Tabarani recorded it in al-Mu'jam al-Kabir. Its chain contains a narrator whom I do not know.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصيام / 4823
Hadith Gradingمحدثین:إسناده ضعیف
Hadith Takhrij«اخرجه الطبراني فى المعجم الكبير (8258) ، أخرجه المعجم الكبير للطبراني برقم: 8258»