WASHINGTON -- The United States will seek a peaceful solution to the North Korean nuclear issue until it becomes necessary to use military force, Washington's top diplomat said Sunday.

Secretary of State Rex Tillerson said the US has been carrying out a "peaceful pressure campaign" to compel North Korea to come to the negotiating table over its nuclear and ballistic missile program.

But if the diplomatic efforts fail, "our military option will be the only one left," he said in an interview on CBS.

"We do not seek regime change, we do not seek the regime collapse, we do not seek an accelerated reunification of the peninsula, and we do not seek a reason to send our forces north of the demilitarized zone," Tillerson said, reiterating the "four no's" behind the peaceful pressure campaign.
 

On Monday, the UN Security Council unanimously adopted new sanctions to punish North Korea for its sixth and most powerful nuclear test on Sept. 3. On Thursday, Pyongyang fired another missile over Japan.

Tillerson said the UN sanctions are designed to prod the regime to come forward for talks.

But they are backed up by a "very strong and resolute military option," he said, before adding, "Be clear, we seek a peaceful solution to this."

In a separate interview on Fox News, President Donald Trump's national security adviser, H.R. McMaster, struck a more urgent tone.

"We're out of road because in the past, the approach taken to the problem of North Korea and (North Korean leader) Kim (Jong-un's) regime over decades has been to enter into long, drawn out negotiations that then deliver an unsatisfactory agreement, an agreement that then the North Korean regime breaks," he said.

Agreements with the North "locked in the status quo as the new normal," according to the general.

"This regime is so close now to threatening the United States and others with a nuclear weapon that we really have to move with a great deal of urgency on sanctions, on diplomacy, and on preparing, if necessary, a military option," he added. (Yonhap)