China's natural disaster administration has said it had detected a magnitude 3.4 quake in North Korea that was a "suspected explosion", raising fears the isolated state had conducted another nuclear bomb test.
The epicentre is roughly the same as that of a previous shallow quake on 3 September, which turned out to be caused by a North Korean nuclear test, the official Xinhua news agency said.
In a statement on its website, China's natural disaster administration said the quake was recorded at a depth of zero kilometers and described it as a "suspected explosion".
U.S. President Donald Trump ordered new sanctions on Thursday that open the door wider to blacklisting people and entities doing business with North Korea, including its shipping and trade networks, further tightening the screws on Pyongyang's nuclear and missile programme. Previous quakes were caused by weapon tests.
After the last test, which North Korea said was a hydrogen bomb, initial reports from the USGS put the tremor at magnitude 5.6 with a depth of 10km but this was later upgraded to magnitude 6.3 at 0km.
Resisting intensifying global pressure, Pyongyang conducted its sixth and largest nuclear test on September 3 and has launched several missiles this year, including two intercontinental ballistic missiles.
The agency said it is analyzing the nature of the quake.
The majority of North Korea's oil likely comes from China, but the exact tally of oil exports remains unknown, as Beijing has not published such data since 2014.
"We have to calm down the hot heads", Lavrov said, adding that he was convinced a Russian-Chinese proposal could still pave the way for a diplomatic solution to the North Korea crisis.
The announcement follows days of increasingly bellicose rhetoric between US President Donald Trump and Kim Jong-Un's regime, which has raised worldwide alarm. At the United Nations, Trump called Kim "rocket man" and threatened to "totally destroy" North Korea.
The sources said lenders were asked to fully implement United Nations sanctions against North Korea and were warned of the economic losses and reputational risks if they did not do so.