South Korea was to announce 50 members of a presidential committee aimed at making preparations for unification with North Korea, an official said Tuesday, amid tensions on the divided Korean Peninsula over Pyongyang's missile launches.

President Park Geun-hye ordered the formation of the preparatory committee in January, saying the country should be prepared for inter-Korean unification which she said would be a "bonanza" for both Koreas as well as a blessing for neighboring countries.

Still, the committee's formation was delayed by a deadly ferry sinking in April that left more than 300 people dead or missing, mostly high school students.

Senior presidential foreign affairs and security secretary Ju Chul-ki was to announce the 50 members later in the day, presidential spokesman Min Kyung-wook said.

The committee, to be chaired by Park, will include not only government officials but also experts from the private sector, according to officials.

The planned announcement comes a day after North Korea fired about 100 artillery shells into the sea off the country's east coast from near the heavily fortified border, in its latest show of force against South Korea.

South Korea said unification would provide the Korean people with a springboard to prosperity by marrying South Korea's capital and technology with North Korea's rich natural resources.

Meanwhile, North Korea has long suspected that Seoul could be plotting to absorb Pyongyang.

The two Koreas have been divided for over six decades following the 1950-53 Korean War, which ended in a cease-fire, not a peace treaty. (Yonhap)