SEOUL - South Korea is preparing to ship medical supplies worth more than $15 million to help North Korea fight an outbreak of swine flu, officials said Monday.

The unification ministry, which handles cross-border ties, said the shipment would include antiviral drugs for 500,000 patients ? Tamiflu for 400,000 and Relenza for 100,000 ? and sanitation supplies.

The aid will cost an estimated W17.8 billion ($15.3 million), which will be financed by a state fund for inter-Korean cooperation, it said.

Spokesman Chun Hae-Sung said Seoul would send the shipment as soon as possible and definitely by the end of the year. But the North, which had accepted the offer, had not yet set a firm date.

North Korea Wednesday reported nine cases of (A)H1N1 in the capital Pyongyang and the city of Sinuiju bordering China. No death toll was given.

The announcement confirmed outside reports of an outbreak in the secretive and impoverished communist state.

The drugs shipment will be the first direct South Korean government aid since relations soured last year, although Seoul has funded assistance to Pyongyang through private groups.

Good Friends, a Seoul-based welfare group with cross-border contacts, quoted an unidentified Sinuiju city official as saying more than 40 people had died of the swine flu in the border city alone.

Observers say the virus could pose a particular threat to the North because of malnutrition amid persistent food shortages and a lack of drugs such as Tamiflu.