A 38-year-old woman from Delhi undergoes colposcopy for abnormal Pap smear. Colposcopic examination reveals a 2 cm acetowhite lesion with coarse punctation and sharp margins in the transformation zone. Directed cervical biopsy confirms CIN 3 (cervical intraepithelial neoplasia grade 3). The lesion does not extend to the margins of the biopsy specimen. What is the most appropriate management?