SINGAPORE - SINGAPORE Telecommunications , Southeast Asia's biggest telecoms firm, reported an 18.8 per cent increase in second quarter profits as core markets performed well and its associate in Indonesia showed strong revenue gains.

SingTel, which owns Optus in Australia and stakes in mobile operators across Asia, has been facing single-digit growth in its core markets of Singapore and Australia. In some of its overseas operations, it faces a squeeze on margins as competition grows from rivals.

The company, around 55 per cent-owned by state investor Temasek , posted July-September underlying net profit before goodwill and exceptionals of $952 million compared with an average forecast of $956 million in a Reuters survey of five analysts.

The quarterly underlying net profit was 18.8 per cent higher than the year-ago's $801 million.

Singapore's biggest company by market value increased its total global subscriber base by a 26 per cent to 273 million as at the end of September, helping boost revenue by 5.4 per cent to $4.1 billion.

SingTel shares are up by around 15 per cent so far in 2009, underperforming a 54 per cent gain on the broader Singapore share index.