Sayyidah Aishah (may Allah be pleased with her) said that after Fajr people would perform tawaf of the House of Allah, then sit down for dhikr. Sayyidah Aishah (may Allah be pleased with her) said: When the prohibited time began, they would stand up and pray.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 4419