Nafi' narrates: When Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) began the prayer, he would recite "Bismillahir-Rahmanir-Rahim" before Surah al-Fatihah, and also recite "Bismillahir-Rahmanir-Rahim" before the surah after it, and he would mention that he had heard this from the Prophet (peace and blessings be upon him).
Al-Tabarani recorded it in al-Mu'jam al-Awsat. Its chain contains a narrator Abd al-Rahman bin Abdullah bin Umar al-Umari, and he is extremely "da'if" (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 2637
Hadith Gradingمحدثین:إسنادہ ضعیف جداً
Hadith Takhrij«أخرجه المعجم الأوسط للطبراني برقم: 845»