TOKYO (Reuters) - Japan posted a current account surplus for the third month in April as the trade deficit narrowed and income gains from overseas investment grew, government data showed, easing worries about declines in the country's balance of payments.

The current account stood at 1.9 trillion yen ($13.58 billion) surplus in April, Ministry of Finance data showed on Thursday, beating economists' median forecast for a surplus of 1.66 trillion yen in a Reuters poll.

It followed a surplus of 2.3 trillion yen in the previous month, the data showed.

A weak yen and rises in global interest rates helped drive up primary income gains from Japanese securities investments overseas, an MOF official said.

That reflected the trend in which the country increasingly earns income from capital parked abroad rather than from sales of goods and services.

The primary income surplus stood at 3 trillion yen, more than enough to offset the trade deficit of 113 billion yen, the data showed.

Over the past year, the current account data often highlighted the pain that high energy costs and a weak yen were inflicting on Japan's economy, the world's third biggest, which relies heavily on imports of fuel and raw materials.

Japan's position as an export powerhouse has also waned in recent years, in part because companies have moved production overseas, making overseas investment a pillar of the country's earning power.

($1 = 139.9600 yen)