BEIJING China said on Thursday the possibility of North Korea conducting a second nuclear test was "hypothetical," so it could not say how it would affect relations.
"We hope that all sides will pay attention to the big picture and appropriately resolve the relevant problems and together protect the progress of the six-party talks process," Chinese Foreign Ministry spokeswoman Jiang Yu said.
On Wednesday, North Korea restated it was pulling out of six-party talks on North Korea grouping the two Koreas, Japan, Russia, the United States and host China.
Jiang's response at a twice-weekly press conference suggested China, North Korea's biggest ally, intends to persevere with its low-key reaction to North Korean statements and deeds.
It was Beijing's first official public response to Pyongyang's statement that it will conduct a nuclear test and also test an intercontinental ballistic missile unless the U.N. Security Council apologizes for imposing sanctions.
China condemned North Korea's only previous nuclear test in 2006.
(Reporting by Chris Buckley; Writing by Nick Macfie)