Umm al-Mu'mineen Sayyidah Hafsah (may Allah be pleased with her) said that it was the habit of the Messenger of Allah (peace and blessings be upon him) that when the muezzin had given the call to prayer after the true dawn had appeared, he would perform two light rak‘ahs between the adhan and the iqamah before the prayer was established (these were the Sunnah of Fajr, which he would always perform whether traveling or at home).

Sayyidah Aisha Siddiqa (may Allah be pleased with her) said that the Noble Prophet (peace and blessings of Allah be upon him) used to offer two light rak'ahs between the call to Fajr prayer and the Iqamah.

Sayyidah Aisha (may Allah be pleased with her) narrated that the Prophet Muhammad (peace and blessings be upon him) used to keep the two (Sunnah) rak'ahs before the (obligatory) Fajr prayer very short. Whether he recited Surah Al-Fatihah in them or not, I cannot say.

Lady Aisha (may Allah be pleased with her) narrated that the Prophet Muhammad (peace and blessings be upon him) was not more regular in offering any voluntary prayer than the two rak'ahs before Fajr.