TOKYO (REUTERS) - Japan is set to relax the age restriction on beef imports from the United States to 30 months, from 20 months currently, as early as Feb 1, the health ministry said on Tuesday, as global concern over mad cow disease ebbs.

The rules, imposed in 2005, permitted US beef imports after a total ban in 2003 after the outbreak of bovine spongiform encephalopathy (BSE), but have caused US imports to plunge and Australian beef to gain market share in Japan's 500,000 tonnes-a-year imported beef market.

"We're due to change the importing restrictions on Feb 1 if a medicine and food panel of experts gives us an approval," Health Minister Norihisa Tamura was quoted as saying by a ministry spokesman.

Japan's food safety watchdog said in a report to the government in October last year that the risk from importing beef from cattle aged 30 months or younger from the United States, Canada, France and the Netherlands would be negligible to human health.

The government has since held a series of public consultations and also held bilateral talks on how the new safety requirements would be met in the supplying countries.