Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) narrates that the Messenger of Allah (peace and blessings be upon him) came out to us while we were praying after Fajr, and he ((peace and blessings be upon him)) said: "There is no prayer after Fajr except two rak'ahs."
Hadith Referenceالمعجم الكبير للطبراني / باب العين / 13234