North Korea has carried out a successful ground test of a new rocket engine to launch satellites, according to its state media.

The country's leader, Kim Jong-un, oversaw the test and ordered preparations for the launch of a satellite to begin, the official Central News Agency (KCNA) said on Tuesday, in what some saw as an indication that the country might soon conduct a long-range rocket launch.

"Here we are a few weeks after the fifth nuclear test and they are testing an engine which, according to North Korea, is a much more powerful single engine," said Al Jazeera's Harry Fawcett, reporting from South Korean capital Seoul. 

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"This is a single rocket which North Korea says has a thrust of 80 tonnes of force," he said. "The South Korean space programme, on the other hand, is endeavouring to get an engine of 75 tonnes of force. So, this does seem to be significant progress by North Korea."

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The United Nations and others view the North's space development project as a cover for tests of missile technology, because ballistic missiles and rockets in satellite launches share similar bodies, engines and other technology.

North Korea is also openly working on developing nuclear-armed missiles capable of striking the US mainland.

Kim directed the ground test of a high-powered engine for a carrier rocket for a geo-stationary satellite at the Sohae Space Centre in the country's northwest, according to KCNA.

He was quoted by state media as ordering officials and scientists to complete preparations for a satellite launch as soon as possible, amid "the enemies' harsh sanctions and moves to stifle", a reference to the United States and the South.

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Jeon Ha-kyu, a spokesman at South Korea's Joint Chiefs of Staff, said South Korea believed the test was for a new engine for a long-range missile.

South Korean media speculated that the North could conduct a long-range rocket launch around October 10, which is the 71st founding anniversary for the North's ruling Workers' Party.

The ground test took place at the Sohae Space Centre in the country's northwest [Reuters]

"The South Korean Defence Ministery has given its reaction [to the launch] this morning at a briefing, saying it does appear to be a new type of engine, higher trust, and it could be used for a missle," Fawcett said.

"They say that they are closely monitoring North Korea, for any signs of further provocations."

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Earlier this month, North Korea conducted its fifth nuclear test, prompting South Korean and US officials to vow to apply more sanctions and pressure on Kim's government. The test explosion, the most powerful to date, was carried out on the 68th anniversary of the founding of North Korea's government.

The toughest UN sanctions in two decades had already been applied agains the North following its fourth nuclear test in January.

North Korea says it needs nuclear weapons and missiles to cope with US military threats. About 28,500 US troops are stationed in South Korea, a legacy of the 1950-53 Korean War which ended with an armistice, not a peace treaty. 

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Source: Al Jazeera News And Agencies