North was accused of sinking a South Korean warship in Mar 2010. And the offer came hours after the United States imposed new sanctions on the North in response to the sinking.
South Korea blames North Korea for sinking the Cheonan on Mar 26 with a torpedo, killing 46 South Korean crew.
South Korea President Lee Myung-bak, has stepped back from its earlier "sunshine" policy of unconditional aid and has refused assistance to the North without clear progress on ending the North's nuclear programmes.
"The aid includes medical kits, emergency food and supplies," a Unification Ministry official said, quoting the Red Cross message sent to North Korea.