China said Thursday that it will not permit chaos on its doorstep, in another thinly-veiled warning to its wayward ally North Korea amid indications that the North is technically ready to conduct a fresh nuclear test.

"Peace and stability is in the immediate interests of China. We will by no means allow war or chaos to occur on our doorstep," China's foreign ministry spokesman Qin Gang told reporters, when asked about the possibility of a fourth nuclear test by North Korea.

The comments by Qin echo those of Chinese leaders, but were the strongest yet by the Chinese foreign ministry in response to recent reports that North Korea appears to have completed technical preparations for a nuclear test.

In Tokyo, U.S. President Barack Obama, who is set to arrive in South Korea on Friday, urged China to do more to rein in North Korea, describing China's role in getting North Korea to abandon its nuclear program as "critical."

Asked about the remarks by Obama in Tokyo, Qin said, "We have been encouraging all relevant parties to peacefully resolve relevant issues through dialogue and consultation."

"We hope that all other parties concerned can bear in mind the larger interests and make joint efforts with China to realize denuclearization, peace and stability on the Korean Peninsula," Qin said.

 North Korea, which conducted three nuclear tests in 2006, 2009 and 2013, threatened last month that it would not rule out "a new form" of nuclear test after the United Nations Security Council condemned Pyongyang for test-firing ballistic missiles into the sea. Outside experts believe that a fourth nuclear test by North Korea may be based on enriched uranium. (Yonhap)