China may be getting fed up with continued nuclear bluster from long-time ally North Korea and tilting toward the United States.
A day after North Korea's Vice Foreign Minister said Pyongyang would test missiles weekly and use nuclear weapons if threatened, a Chinese Foreign Ministry spokesman said Beijing was "gravely concerned" about North Korea's recent nuclear and missile activities.
In the same press conference, spokesman Lu Kang praised recent US statements on the North Korean issue.
"American officials did make some positive and constructive remarks... such as using whatever peaceful means possible to resolve the (Korean) Peninsula nuclear issue. This represents a general direction that we believe is correct and should be adhered to," Lu said.
That direction was not evident from North Korean leadership, as state-run TV highlighted a propaganda video showing missile strikes leaving the US in flames.
North Korean Vice Foreign Minister Han Song-ryol ratcheted up the rhetoric in an interview with the BBC.
"If the United States is reckless enough to use military means, it would mean from that very day an all-out war," Han said.
Statements of that vein do not help the situation, according to the Chinese Foreign Ministry spokesman.
"China firmly opposes any words or actions that would escalate rivalry and tension," Lu said.
US President Donald Trump has been pressing China to rein in North Korea, suggesting that doing so could ease US-China relations over trade and other issues.
Experts point out that China also wants to prevent North Korea from becoming a full-fledged nuclear power -- and certainly wants to prevent a war on its southern border that could send millions of refugees flooding into China and potentially risk bringing a US military presence to China's borders.
Earlier this year, China called on the US and North Korea to give up something to ease tensions on the Korean Peninsula. The US, along with South Korea, should suspend annual military exercises that antagonize North Korea in exchange for Pyongyang halting its nuclear program, China's Foreign Minister Wang Yi said in early March.
Since then, North Korea has continued its missile testing, including one fired just before an early April summit between Trump and Chinese President Xi Jinping, staged a large-scale military parade with new missiles and launchers, and pledged to test another nuclear weapon at any time.
The US, meanwhile, has conducted missile defense drills with the South Korean and Japanese navies, sent its newest F-35 stealth fighters to train in South Korea, flown B-1 bombers to South Korea, and just Thursday commenced "Max Thunder," billed as the second-largest military flying exercise between US and South Korean forces.
The Pentagon has also dispatched the aircraft carrier USS Carl Vinson strike group to the Korean Peninsula.
North Korea's official Korean Central News Agency called the carrier's deployment "nothing but a reckless action of aggression to aggravate the tensions in the region."
When asked about the Vinson's movements Wednesday, Lu was measured in his response, reiterating at one point, "we maintain close contacts with the US on the current situation."
The language on North Korea's nuclear program was more straightforward.
"China's position on opposing a nuclear-capable (North Korea) is firm, clear and consistent," Lu said.