South Korea launches rocket amid tensions with North

The launch comes hot on North Korea's heels after North Korea deployed its own three-stage rocket just weeks ago, sparking international criticism.

Named Naro, South Korea's 140-tonne rocket , was partly built by South Korea and partly in Russia, which has said it will partner with Seoul for three attempts.

Previous launch attempts in 2009 and 2010 failed, and this attempt has been postponed twice for technical reasons.

South Korea's rocket programme has angered neighbour North Korea, which regretted the fact that there being singled out for U.N. sanctions for launching long-range rockets as part of its space programme to put a satellite into orbit.

North Korea showed it's capability deliver a rocket that could travel 10,000 km, in Decmber. Such a rocket could potentially put San Francisco in range, according to an intelligence assessment by South Korea.

Officials confirmed that Wednesday's launch from the site 480km south of Seoul had gone as planned, Yonhap news agency reports.

"The launch of the rocket itself succeeded," an official told Yonhap. But it is not yet possible to determine whether the satellite was in its correct orbit.

The satellite, called Science and Technology Satellite-2C, is designed to collect climate data. It is expected to make contact with its ground station at 05:00 on Thursday, at which point its operators will be able to determine whether it is in the right place and functioning properly.

South Korea is struggling to keep up with regional rivals China and Japan in the effort to build space rockets to put satellites into orbit and has relied on other countries, including Russia, to launch them.

South Korea intends to build a rocket on its own by 2018 and eventually send a probe to the moon.