Singapore Telecommunications (SingTel) has bought an additional 1.52 per cent stake in Bharti Airtel, increasing its stake in the Indian operator from 30.43 per cent to 31.95 per cent. The Singapore-based firm will pay up to Rs 30.08 billion for the stake in three instalments over an 18-month period. SingTel is buying the additional stake through its subsidiary Pastel, which has entered into a conditional share-purchase agreement with the Bharti Group to purchase 730,000 issued shares in Bharti Telecom, a subsidiary of Bharti Airtel.