Ibn Az-Zubair said to him: "Narrated to me from what the Mother of the Believers used to (secretly) inform you about" - meaning Aishah - so he said: "She narrated to me that the Messenger of Allah said: 'Had your people not been still close to the pre-Islamic period of ignorance, then I would demolish the Ka'bah and rebuild it with two doors.'" He said: "So when Ibn Az-Zubair came to power he demolished it and rebuilt it with two doors."
Jami` at-Tirmidhi Book 9, Hadith 68
← Previous Hadith "The Prophet performed Salat in the interior of the Ka'bah." And Ibn Abbas said: "He did not perform Salat in it, but he said the Takbir."

Jami` at-Tirmidhi Book 9, Hadith 67 Next Hadith → "I wanted to enter the House to perform Salat in it, so the Messenger of Allah took me by the hand and put me in the Hijr, and he said: 'Perform Salat in the Hijri if you want to enter the House. For indeed it is part of the House, but your people considered it insignificant when they built the Ka'bah, so they put it outside the House.'"

Jami` at-Tirmidhi Book 9, Hadith 69