30 January 2013 Last updated at 04:50 ET

The BBC's Lucy Williamson says the launch will be met with relief in Seoul

Previous launches in 2009 and 2010 failed, and this attempt had been postponed twice for technical reasons.

But officials said Wednesday's launch from the site 480km (298 miles) south of Seoul had gone as planned and that the rocket had reached its target altitude and deployed its satellite.

"After analysing various data, the Naro rocket successfully put the science satellite into designated orbit," Mr Lee told reporters. He said the satellite had detached 540 seconds after launch.

"We now have leapt up a step to become a space-power nation," he said, adding that South Korea would use this "overwhelming moment as a strong, dynamic force" to help drive an independent space programme.

The satellite, called Science and Technology Satellite-2C, is designed to collect climate data. The Yonhap news said it was expected to make contact with its ground station at 05:00 on Thursday, at which point its operators will be able to make the final judgement on whether the launch achieved its goals.

South Korea does already have satellites in space, but they were launched from other countries.

On its first attempt to carry out a launch on its own soil, in 2009, the satellite failed to detach from the rocket in orbit. In 2010, the rocket exploded seconds after take-off.

Pressure for success has increased since North Korea launched a rocket that placed a satellite in orbit on 12 December. It followed the launch by announcing plans for a "high-level nuclear test" and more long-range rocket launches.

The UN said the North Korean launch constituted a banned test of missile technology and voted to extend sanctions against Pyongyang. There have been international calls for Pyongyang not to carry out the nuclear test.