Fresh UN sanctions come amid ASEAN meeting, where Chinese minister is urging North Korean official to abide by measures.
US Secretary of State Rex Tillerson on Sunday praised the approval of new UN sanctions agreed a day earlier, calling the move a "very good outcome."
The Security Council unanimously adopted the US-led resolution, which bans mineral and seafood exports worth more than $1bn, after North Korea tested two intercontinental ballistic missiles (ICBM) last month.
China's Foreign Minister Wang Yi said the sanctions were the right response, but repeated a call for dialogue.
South Korean Foreign Minister Kang Kyung-wha echoed Tillerson's praise for the approved sanctions as a "very, very good outcome".
Meanwhile, Japan said it was time to exert more "efffective pressure" on Pyongyang rahter than to pursue dialogue.
"Now is not the time for dialogue but the time to increase effective pressure on North Korea so that they will take concrete actions towards de-nuclearisation," deputy foreign ministry spokesman Toshihide Ando told a news conference in Manila.
The diplomats are meeting in Manila, the Philippine capital, as foreign ministers from across Asia gather for a regional ASEAN summit.
Tillerson said he and his South Korean counterpart plan to discuss the sanctions during their meeting, along with next steps to pressure North Korea.
Washington wants eventually to talk to North Korea, Tillerson has said, but thinks such discussions would be futile if Pyongyang intends on maintaining its nuclear weapons.
The US secretary of state is also due to meet diplomats from China and other countries central to the North Korea debate.
Jean Lee, a fellow at the Wilson Centre, said it was "not the right time" for Tillerson to engage with his North Korean counterpart.
"The US and its allies will be looking for some proof and concrete steps taken by the North Korean side to show that they are willing to discuss a freeze or step back from the nuclear provocations, before they even begin discussing engagement," she told Al Jazeera from Seoul, South Korea's capital.
China urges 'calm'
Meanwhile, Wang held bilateral talks with North Korea's top diplomat, Ri Yong-ho, on the sidelines of the ongoing Manila summit.
"We had an intensive conversation, China urges North Korea to remain calm in dealing with the recent decision given by the UN Security Council," the Chinese minister said, adding he urged North Korea not to violate the UN decision.
"We would like to urge other parties, such as the US and South Korea, to stop increasing tensions. The Korean Peninsula's situation has reached a critical point. In the meantime, it's also a turning point for resuming negotiations," he said. "At this critical moment, we urge every party to remain calm, to take a decision that helps to reduce tensions, resume negotiations and secure regional peace development."
When asked by a journalist about North Korea's reaction, Wang said: "I think you have already anticipated North Korea's reaction."
China's Foreign Minister Wang Yi, right, shakes hands with North Korea's Foreign Minister Ri Yong-ho before their bilateral meeting [Reuters]
China's vote on new UN sanctions helped clear the way for the 15-0 vote on Saturday.
Al Jazeera's Rob McBride, reporting from Beijing, said that China is always careful when dealing with North Korea.
"The last thing China wants to see is North Korea being pushed to the point of its own self-destruction," he said. "That is almost a worst-case scenario."
US President Donald Trump on Saturday touted the new UN measures, saying they will have a "very big financial impact".
He wrote on Twitter: "The United Nations Security Council just voted 15-0 to sanction North Korea. China and Russia voted with us. Very big financial impact!"
A few hours later, the US president commended the Security Council and said he appreciated the cooperation of China and Russia in passing the resolution, White House press secretary Sarah Huckabee Sanders said in a statement.
Source: Al Jazeera and news agencies