A 58-year-old woman undergoes low anterior resection with total mesorectal excision for a mid-rectal adenocarcinoma. Intraoperatively, the surgeon notes that the tumour is adherent to the left ureter. The ureter is carefully dissected free, but a small full-thickness defect is created during mobilization. Which of the following is the most appropriate immediate management of this iatrogenic ureteric injury?