Japan's service industry activity index jumped 1.8 percent in April from the previous month to mark the first rise in three months, the government said Thursday.

The improvement was led by favorable business results at trading companies and car dealers, the government said.

The tertiary industry index -- a measure of demand for services -- came to a seasonally adjusted 107.1 against the 2000 base of 100, compared with 105.2 in March, the Ministry of Economy, Trade and Industry said in a preliminary report.

Of the 11 sectors covered by the report, activity indexes grew in five sectors, with wholesale and retail sales making the biggest contribution to the rise. The information and telecommunications sectors, as well as transport services, also posted gains.