(Corrects to say profit fell by 64%, not 280%, in paragraph 1)

(Reuters) - Singapore Telecommunications on Thursday posted a 64% drop in full-year net profit hit by a S$3.1 billion ($2.30 billion) impairment charge, majority of which relates to its mobile network operation unit Optus. Southeast Asia's largest telecom firm said net profit for fiscal 2023 was S$795 million, compared with S$2.23 billion a year ago.

(Reporting by Ayushman Ojha and Shivangi Lahiri in Bengaluru; Editing by Shailesh Kuber)