SEOUL, South Korea - South Korea prepared to launch its first rocket, just four months after rival North Korea defiantly launched its own and quickly was slapped with U.N. sanctions.
The North has warned it would closely watch the international response to South Korea's launch, scheduled for later Wednesday.
In April, the North claimed it shot a satellite into orbit and was angered when the U.S., Japan and South Korea called it a disguised test of the regime's U.N.-banned ballistic missile technology.
South Korean officials have said their rocket launch, carrying an observation satellite, is peaceful, and they hope it will boost the country's aim to become a regional space power.
The launch of its first rocket, built in co-operation with Russia, was to take place from its space centre on an island about 290 miles (465 kilometres) south of Seoul, according to the Science Ministry.
If successful, it would also mark South Korea's first launch of a rocket into space from its own territory. Since 1992, it has launched 11 satellites from overseas sites, all on foreign-made rockets.
Science Ministry official Yeom Ki-su said the two-stage rocket, called KSLV-I, will carry a domestically built satellite aimed at observing the atmosphere and ocean.
The launch was initially set for July 30 but has been delayed twice due to technical glitches, Yeom said.
Rival North Korea has already developed a variety of missiles, and the multistage rocket it launched in April is believed theoretically capable of reaching the western U.S.
The North's Foreign Ministry said in a statement last week that it will "closely watch" how the U.S. and other neighbouring countries respond to the South's launch.
In Washington, State Department spokesman Ian Kelly told reporters Tuesday that the United States has regularly consulted with South Korea on security issues.
"The South Koreans have developed their program in a very open and transparent way. And in keeping with the international agreements that they have signed on to, this is in stark contrast to the example set by North Korea, which has not abided by its international agreements," Kelly said.
Moon Tae-young, a spokesman at South Korea's Foreign Ministry, said Monday that the launch was for peaceful purposes and would be conducted transparently.
Moon said it was not appropriate to compare it with the North's April launch.
The Science Ministry said in a statement earlier this year that South Korea aims to develop a space launch vehicle with its own technology by 2018 and a lunar module by 2025.
China, Japan and India are Asia's current space powers. Japan has launched numerous satellites, India has a satellite orbiting the moon and China sent astronaut Yang Liwei into space in 2003.
