Higher handset subsidies and base station related costs ate into mobile operator M1's profits, which fell 10 per cent to $146.5 million for the year ended Dec 31, 2012.

Capital expenditure incurred for the year was also higher at $122.5 million mainly due to the upgrade of its billing and customer care system, as well as the expansion of its mobile network coverage and capacity.

Revenue rose by 1 per cent to $1.07 billion for the year due to higher mobile service revenue, it announced on Monday.

The telco grew its mobile customer base by 50,000 during the last three months of last year to 2.109 million.