A South Korean soldier looks through a pair of binoculars near the border village of Panmunjom, which has separated the two Koreas since the Korean War, in Paju, South Korea, on Thursday. In response to North Korea's latest nuclear test, South Korea on Thursday announced it would resume cross-border propaganda broadcasts that Pyongyang considers an act of war. Photo: AP

China on Thursday expressed concern over the current developments on the Korean Peninsula, urging all members of the Six-Party Talks to return to the negotiation table after South Korea and the US discussed deploying strategic weapons in response to North Korea's nuclear test.

Analysts believe the deployment on the Korean Peninsula will further aggravate tensions in Northeast Asia and risk upsetting China and Russia.

Peace and stability on the Korean Peninsula and in Northeast Asia meet the common interests of all concerned, foreign ministry spokeswoman Hua Chunying said Thursday at a regular press briefing.

China is determined to advance denuclearization on the Korean Peninsula and settle the nuclear issue through the Six-Party Talks, she said.

The talks stalled in 2008, with the North quitting the process in 2009.

South Korea's Joint Chiefs of Staff Chairman Lee Sun-jin and US Forces Korea commander Curtis Scaparrotti on Wednesday discussed the deployment of US strategic assets on the Korean Peninsula, including a nuclear-powered submarine, the F-22 stealth combat fighter and the B-52 bomber, a South Korean military official said Thursday. 

South Korea also said it would resume propaganda broadcasts by loudspeaker into North Korea from Friday, which is likely to infuriate Pyongyang, Reuters reported.

"The military deployment is possible as the US will not dismiss the chance to expand its military presence in the Asia-Pacific region, neither will its ally Japan," Lü Chao, a researcher at the Liaoning Academy of Social Sciences, told the Global Times.

Moreover, the US is overreacting as military deployment would only aggravate tensions in the region and the situation may spiral out of control, especially if there are any incidents, he said. 

US President Barack Obama spoke to his South Korean counterpart Park Geun-hye Thursday. The two agreed to forge a united and strong international response and that North Korea should pay the corresponding price, the Yonhap News Agency reported.

Obama also said the US would take measures to ensure the security of its allies, including Japan, during a phone conversation with Japanese Prime Minister Shinzo Abe Thursday morning, the Xinhua News Agency reported.

After North Korea last tested a nuclear device in 2013, Washington sent a pair of nuclear-capable B-2 stealth bombers on a sortie over South Korea in a show of force. At the time, North Korea responded by threatening a nuclear strike on the US.

North Korea's official media announced it had successfully conducted its first hydrogen bomb test at 10 am on Wednesday, its fourth nuclear test.

No pollution

Separately, US Republican presidential candidate Donald Trump said on Wednesday that China should take the lead in tackling North Korea, Reuters reported Thursday.

"China has total control," Trump said on Fox News. "They have total control over North Korea, and China should solve that problem. And if they don't solve the problem, we should make trade very difficult for China."

"Trump is being ignorant and ridiculous. China was not informed in advance and has also been a victim of the test as a neighbor of North Korea," said Lü.

The test site, in the northeast of the country at the Punggye-ri nuclear site, is only 100 kilometers from the Chinese border.

According to sample tests on water, air and soil in Northeast China's border cities, together with weather forecasts for the coming week, North Korea's nuclear test will not cause any pollution in China, the Ministry of Environmental Protection announced on its website Thursday.

The US should take the major responsibility, said Lü, as according to the North Korean statement, the test was mainly targeting the US. It was also a result of the failed US policy to hold a contradictory approach to address the nuclear issue of North Korea.

The US, European Council members and Japan would seek to expand existing UN sanctions against Pyongyang if the latest North Korean nuclear test was confirmed, several Western diplomats said, Reuters reported.