The Bharti Airtel stock was up two per cent after the company announced it had completed the sale of telecom towers in five African countries for a consideration of about $1.3 billion. The company has said it will use the proceeds to reduce its net debt, currently stands at $11 billion. Including the deferred payments, the total debt is pegged at $15 billion or Rs 90,000 crore by analysts. At the current net debt level, the sale should bring down debt by about 12 per cent and help save interest costs. Interest costs increased to Rs 5,013 crore in FY15, from Rs 3,660 crore in FY14.