عَنْ عَائِشَةَ رَضِيَ اللَّهُ عَنْهَا قَالَتْ قُبِضَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ وَلَمْ يَسْتَخْلِفْ أَحَدًا وَلَوْ كَانَ مُسْتَخْلِفًا لَاسْتَخْلَفَ أَبَا بَكْرٍ أَوْ عُمَرَ رَضِيَ اللَّهُ عَنْهُمَا
It is narrated from Sayyidah Aisha (may Allah be pleased with her) that the Messenger of Allah (peace and blessings be upon him) departed from this world and he (peace and blessings be upon him) did not appoint anyone as a caliph. If he (peace and blessings be upon him) were to appoint anyone as a caliph, he would have appointed Sayyiduna Abu Bakr (may Allah be pleased with him) or Sayyiduna Umar (may Allah be pleased with him).