North Korea acknowledged for the first time Wednesday that swine flu has hit the nation, a day after South Korea's president offered to help the impoverished neighbor fight the virus reported to have already killed dozens.

The North's Ministry of Public Health confirmed nine cases of swine flu in the border city of Sinuiju, near China, and in the capital, Pyongyang, according to the official Korean Central News Agency.

"The relevant agency is further perfecting the quarantine system against the spread of this flu virus while properly carrying out the prevention and medical treatment," KCNA said.

It is the first time that the reclusive North has confirmed a swine flu outbreak in the country. The regime has remained silent despite reports that the virus already has killed more than 40 people in Sinuiju and Pyongyang and was spreading fast.

The acknowledgment came a day after South Korean President Lee Myung-bak offered to "unconditionally" help North Korea if reported outbreaks were true. Lee instructed the Cabinet to check the reports and study ways to send swine flu medication in humanitarian aid.

The Unification Ministry said it would consider sending a message to the North for talks on the issue.

Lee has halted unconditional aid to the North since taking office early last year, prompting Pyongyang to suspend reconciliation talks and other joint projects in protest. Still, Lee has said he is willing to provide limited amounts of humanitarian assistance.

The two sides remain in a state of conflict, with the 1950-53 Korean War ending in a truce, not a peace treaty.