Anas bin Malik (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings be upon him) prayed four rak'ahs of Zuhr in Madinah and two rak'ahs of Asr at Dhu al-Hulayfah, and I heard them all calling the talbiyah for Hajj and Umrah.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الحج / 8832