Japan's industrial production rose for the third straight month in June as the world's third biggest economy stages a recovery from the March 11 earthquake and tsunami.

Factory output climbed 3.9% from the previous month and is expected to continue growing in the months ahead.

Cars and electronic parts helped fuel the improvement, according to the Ministry of Economy, Trade and Industry.

Industrial production is a key indicator of Japan's economic health, and its steady climb suggests that manufacturers are restoring capacity after the tsunami wiped out towns along Japan's north east coast and damaged critical parts factories.

The disruption led to a big plunge in output for Japanese manufacturers such as Toyota and industrial production is still 5.3% lower than it was in February before the disasters.

Shipments jumped 8.5%, which lowered inventories by 2.8%. That implies "further upside for production in the months ahead", said Kyohei Morita, chief economist at Barclays Capital Japan, in a report.

Despite mandatory summer power cuts, companies surveyed by the ministry expect output to rise 2.2% in July and 2% in August.

The government has ordered large users in the Tokyo area to reduce power usage by 15% until September 22.

Electricity is in short supply because of the Fukushima Dai-ichi nuclear power plant was crippled by the tsunami.

The encouraging figures about industry stand in contrast to more sobering data about jobs and households.

Japan's seasonally adjusted unemployment rate rose slightly to 4.6% from 4.5% in June, the Ministry of Internal Affairs and Communications said.

But the result does not include data from three hardest-hit prefectures - Fukushima, Miyagi and Iwate - where the number of jobless people surged after the disaster.

Monthly household spending fell 4.2% from a year earlier, and monthly household income fell 6.7% in real terms to 687,212 yen (8,800 US dollars).

The government also said core consumer prices in June climbed 0.4% from a year earlier. Higher fuel prices pushed up the figure, which excludes fresh food.