South Korea has approved private humanitarian aid to North Korea, an official said Tuesday, despite tensions on the Korean Peninsula.

The two private aid groups are allowed to ship powered milk and nutritional supplies worth 215 million won (US$202,000) to infants, children and pregnant women in North Korea, said an official of the Unification Ministry handling inter-Korean affairs.

The planned aid brought the total amount of assistance to the North by South Korea's private aid groups to 6.55 billion won since February when President Park Geun-hye took office in Seoul.

The latest aid plan came just days after North Korea threatened to mercilessly strike South Korea "without notice" if anti-North Korean protesters repeat their insult to North Korean leader Kim Jong-un.

Last week, some 70 South Korean protesters burned effigies of the current and former leaders of North Korea as they condemned the young leader Kim Jong-un for his reign of terror.

The North executed Kim's once-powerful uncle, Jang Song-thaek, who had long been considered the North's No. 2 man and Kim's regent, for treason.

The North has bristled at any outside criticism of its leader and has made similar verbal threats against the South in recent years, although no actual attack has occurred since late 2010. (Yonhap News)