US Ambassador Nikki Haley said Washington will present a new sanctions resolution to the council to be negotiated in the coming days, with a view of voting on it next Monday.
"Only the strongest sanctions will enable us to resolve this problem through diplomacy," Haley told an emergency council meeting called by the United States, Britain, France, Japan and South Korea.
German Chancellor Angela Merkel and US President Donald Trump also agreed to push for further sanctions against North Korea after Pyongyang's latest nuclear test, Merkel's office said.
The two leaders during a phone call "shared the view that the international community needs to increase pressure on the North Korean regime and that the UN Security Council must swifty adopt new and harsher sanctions," a spokesman said in a statement.
Global alarm
North Korea on Sunday triggered global alarm when it detonated what it described as a hydrogen bomb designed for a long-range missile.
The underground blast had a yield of between 50 and 100 kilotons, or on average more than five times more powerful than the bomb detonated over Hiroshima, UN political affairs chief Jeffrey Feltman told the council.
Declaring that "enough is enough," Haley said incremental sanctions imposed on Pyongyang since 2006 had failed and accused North Korean leader Kim Jong-Un of "begging for war."
"War is never something the United States wants. We don't want it now. But our country's patience is not unlimited," she declared.
"North Korea has basically slapped everyone in the face in the international community that has asked them to stop."
