Secretary of State Rex Tillerson took the escalating threat of a nuclear North Korea to the United Nations Security Council Friday, urging member countries to financially cut ties with Pyongyang and freeze access to funds that could be used to build up that nation’s nuclear arsenal.

Tillerson called on the international community to fully implement U.N. sanctions and to suspend or downgrade diplomatic ties as well with North Korea.

“With each successive detonation and missile test, North Korea pushes northeast Asia and the world closer to instability and broader conflict," Tillerson said. "The threat of a North Korean attack on Seoul or Tokyo is real."

Tillerson added that it was “only a matter of time” before Pyongyang takes aim at the United States and said the international community must take concrete steps now in order to prevent North Korea from making good on threats.

“Business as usual is not an option,” Tillerson told 15 top diplomats at the U.N. meeting.

The secretary of state’s comments capped off an intense week in Washington that included closed-door briefings between the Trump administration and U.S. lawmakers over the escalating threat.

The Trump administration is hoping to pressure North Korea into dismantling its missile and nuclear programs by “tightening economic sanctions and pursuing diplomatic measures with our allies and regional partners.”

Tillerson said nations should also downgrade their diplomatic relations with North Korea and said the U.S. would “not hesitate to sanction third-party countries.”

U.N. Secretary General António Guterres, who also joined Tillerson on the decision-making council, condemned North Korea’s record of violations of the body’s resolutions over nuclear and missile testing and development.

“I am alarmed by the risk of a military escalation in the region, including by miscalculation or misunderstanding,” he said.

Also speaking at the United Nations meeting was China’s Foreign Minister Wang Yi who pledged that Beijing would fully implement all U.N. sanctions on North Korea.

“Due to the recent efforts by [North Korea] to accelerate missile and nuclear development, China agrees to the international community to step up efforts of non-proliferation,” Wang said.

On Thursday, Tillerson told Fox News he favored diplomatic sanctions as a way to get North Korea to fall in line. Tillerson’s call for sanctions came as President Trump indicated direct conflict with the rogue regime is possible.

“There is a chance that we could end up having a major, major conflict with North Korea. Absolutely,” Trump told Reuters in a wide-ranging interview.

Trump’s comments came on the same day Pyongyang released a propaganda video that simulates an attack on the White House.