China has urged the United States and North Korea to "hit the brakes" on threatening words and work towards a peaceful resolution of a stand-off over Pyongyang's recent missile tests and threats to fire them towards Guam.
The dispute has also raised fears in South Korea, where a conservative political party called for the United States to bring back tactical nuclear weapons to the Korean Peninsula.
Chinese foreign minister Wang Yi said in a phone conversation with his Russian counterpart, Sergey Lavrov, that the two countries should work together to contain tensions and permit no-one to "stir up an incident on their doorstep".
Mr Wang said: "The most important task at hand is for the US and North Korea to 'hit the brakes' on their mutual needling of each other with words and actions, to lower the temperature of the tense situation and prevent the emergence of an 'August crisis'."
Russia said it is against further tightening sanctions on North Korea, warning that economic pressure on Pyongyang has reached its limit.
Mr Lavrov warned "we can't support ideas by some of our partners to suffocate North Korea economically with all the negative and tragic humanitarian consequences for its citizens".
He added that the "potential for economic pressure has been practically exhausted" and emphasised the need to encourage political settlement.
The Russian foreign minister reaffirmed a call by China and Russia for the US to suspend forthcoming annual military exercises with South Korea in exchange for Pyongyang halting its missile and nuclear tests as a first step toward direct talks.
China is North Korea's main economic partner and political backer, although relations between Beijing and Pyongyang have deteriorated amid the North's continuing defiance of China's calls for restraint.
In recent months, China has joined with Russia in calling for the US to suspend the annual military drills, which enrage North Korean officials every year.
Meanwhile, the chairman of the US Joint Chiefs of Staff, Marine Corps General Joseph Dunford, continued a visit to China following talks the day before with his Chinese counterpart that touched on North Korea.
Speaking to reporters after viewing a Chinese military exercise outside the north-eastern city of Shenyang, Gen Dunford said he told General Fang Fenghui that the US hoped diplomatic and economic pressure would convince North Korea to end its nuclear programme, but that it was also preparing military options.
He said: "We hope for a peaceful resolution but we needed to seriously have a conversation about what might happen if there was military action."
His visit to Asia comes after President Donald Trump last week declared the US military "locked and loaded" and threatened to unleash "fire and fury" if North Korea continues to show hostility towards America.
North Korea's military presented leader Kim Jong Un with plans to launch missiles into waters near the US territory of Guam and "wring the windpipes of the Yankees", even as both Koreas and the United States signalled their willingness to avert a deepening crisis, with each suggesting a path toward negotiations.
Mr Trump tweeted on Wednesday that Mr Kim had "made a very wise and well reasoned decision", amid indications North Korea had decided not to proceed with its multiple missile launch.
"The alternative would have been both catastrophic and unacceptable!" Mr Trump wrote.
During an inspection of the North Korean army's Strategic Forces, which handles the missile programme, Mr Kim praised the military for drawing up a "close and careful plan" and said he would watch the "foolish and stupid conduct of the Yankees" a little more before deciding whether to order the missile test, state media said.
Mr Kim appeared in photos sitting at a table with a large map marked by a straight line between what appeared to be north-eastern North Korea and Guam, and passing over Japan - the missiles' apparent flight route.
The tentative interest in diplomacy follows unusually combative threats between Mr Trump and North Korea amid worries Pyongyang is nearing its long-sought goal of being able to send a nuclear missile to the US mainland.
The US-South Korean military exercises are due to start next week.