In a rare public warning to its unruly ally North Korea, China on Tuesday urged the North not to carry out a nuclear test, saying it does not support Pyongyang's "threat of a nuclear test."

The public warning by China's foreign ministry spokeswoman Hua Chunying came as tensions on the Korean Peninsula spiked again, with the North continuing to threaten additional missile and a "new form" of nuclear tests.

 "We do not support the joint military drills (between South Korea and the U.S.) and do not support the threat of a nuclear test (by North Korea)," Hua told reporters during a regular press briefing, when asked about the current tensions on the Korean Peninsula.

 While China has long voiced opposition to annual military drills between South Korea and the U.S., it is rare for Beijing to issue a pointed warning to North Korea over possible provocations. 

Describing the situation on the peninsula as "quite fragile,"

Hua said, "We oppose any actions that may escalate tensions." 

"China continues to play a positive role in making the Korean Peninsula have a soft landing," Hua said. "Meanwhile, we hope relevant parties to bear in mind the big picture and do things that are conducive to building mutual trust and easing tensions." 

In recent weeks, North Korea has conducted a series of artillery and ballistic missile launches, widely seen as acts of protest joint South Korea-U.S. military drills that are scheduled to end this week. 

The U.N. Security Council condemned last month the North's tests of two midrange ballistic missiles, but stopped short of imposing new sanctions. 

North Korea raised the ante on March 31 by announcing that it might carry out a "new form of nuclear test," indicating it might detonate a uranium-based device. (Yonhap)