China voices NK concerns A North Korean soldier stands guard in front of the Unha-3 rocket at the Tongchang-ri Space Center on Sunday.(AFP...

China voices NK concerns

A North Korean soldier stands guard in front of the Unha-3 rocket at the Tongchang-ri Space Center on Sunday.(AFP)

China again expressed concerns Sunday over the development of the situation on the Korean Peninsula, as some 30 foreign reporters have arrived in North Korea for the upcoming satellite launch.

During the sixth trilateral foreign ministers' meeting between China, Japan and South Korea in Ningbo, Zhejiang Province, Chinese Foreign Minister Yang Jiechi urged all parties to remain calm and exercise restraint over Pyongyang's satellite launch set to take place between April 12 and 16.

"China will maintain close communication and coordination and work with parties to play a constructive role in upholding overall peace and stability of the region and advancing the Six-Party Talks process," Yang told his South Korean counterpart, Kim Sung-hwan, and Japanese counterpart, Koichiro Gemba.

According to the Xinhua News Agency, the rocket for Pyongyang's planned satellite mission has been installed on the launch pad.

A North Korean official told Xinhua correspondents at the scene Sunday that the Unha-3 rocket has not been fuelled yet.

Xinhua was among the foreign media invited to visit the launching station, control and command center and other facilities.

The Korean Central News Agency (KCNA) reported Saturday that some 30 foreign reporters from around the world are in Pyongyang to cover the launch.

The aerospace agencies of Russia, US and Japan rejected North Korean's invitation to send observers to Pyongyang, according to previous media reports.

On March 16, Pyongyang announced its plan to launch the Kwangmyongsong-3 satellite to mark the 100th birthday of late leader Kim Il-sung.

Gemba said Sunday that the key result from the Ningbo talks was a plan to continue to work together to stop the launch, while Kim Sung-hwan warned that the launch would be a backward step for Pyongyang.

Lü Chao, director of the North and South Korean Research Center at the Liaoning Academy of Social Sciences, told the Global Times that the planned rocket launch had worsened tensions on the peninsula, but admitted little could be done to stop it.

"The West does not have countermeasures except for more sanctions. How to deal with North Korea in the future remains an issue for the international community," Lü said.

Also Sunday, South Korea's Yonhap News Agency reported that North Korea was "clandestinely preparing a nuclear test" at the same location as the first two.

An unidentified intelligence source told the agency that workers had been seen in commercial satellite images digging a tunnel in the northeastern town of Punggye-ri, Kilju county, adding to existing mines believed to have been used for tests in 2006 and 2009.

"We have confirmed the (mining) work is coming to its final stage," the source was quoted as saying.

The satellite imagery showed piles of earth and sand at the entrance of the tunnel, Yonhap reported.

Meanwhile, the KCNA reported developments in North Korea in line with the government's pledge to open the door to a "powerful and prosperous country" in 2012.

North Korea's Huichon power station started operation Friday, which will help ease electricity shortages in the capital. Besides, massive construction projects in Pyongyang, such as high-rise residential compounds, are also being accelerated, according to the KCNA.

"The Huichon power station is a great accomplishment for the North. The construction was originally planned to take 10 years, but it only took three years to complete the whole project in order to catch up with the anniversary of Kim Il-sung's birthday," Lü said.

"However, despite these tiny improvements, the overall economy still operates at a low level, and North Korea's high spending on defense, including its investments in rocket and nuclear systems, is one of the factors that add burdens to its growth."

"Under such circumstances, the North needs a morale booster such as the planned rocket launch," Lü added.

Japanese Prime Minister Yoshihiko Noda has given the green light to shoot down the rocket if it threatens Japan's territory.

Patriot missiles were deployed Saturday at the defense ministry in downtown Tokyo and at two other bases in the region to protect the greater Tokyo area.

Seoul has also warned it might shoot down any parts of the North Korean rocket heading for its territory.