The United States does not seek a regime change in North Korea, Secretary of State Rex Tillerson said Tuesday, as tensions renewed over the country's nuclear and missile programs.

North Korea conducted its second test of an intercontinental ballistic missile last week, fueling concerns that the communist nation may be close to delivering a nuclear weapon to the US mainland.

Pyongyang said the test was aimed at giving a "stern" warning to the US, which is bent on employing sanctions and pressure on North Korea and justifies the regime's will to develop nuclear weapons with threats of war.

"We do not seek a regime change. We do not seek the collapse of the regime," Tillerson said in a surprise appearance at a State Department press briefing. "We do not seek an accelerated reunification of the peninsula. We do not seek an excuse to send our military north of the 38th parallel."

North Korea claims the regular military drills by South Korean and US troops are a precursor to an invasion of the North. To deter US aggression, it insists on developing its nuclear and missile programs. The 38th parallel refers to the inter-Korean border.

Tillerson said one of the first threats the Donald Trump administration faced was that posed by North Korea.

"That threat has materialized in the ways that we expected it would," he said. "That's why, early on, we identified it as a very urgent matter and the North Koreans have certainly proven the urgency of that to us."

After last week's launch, which followed an earlier test on July 4, Pyongyang claimed its missiles can range the entire US

mainland. By some estimates in the US, North Korea could master the technology to field a nuclear-tipped ballistic missile as early as next year.

The secretary said the administration pursued a campaign of "peaceful pressure" on Pyongyang in the hopes that the regime would want to sit and talk about its nuclear program.

"But with an understanding that a condition of those talks is there is no future where North Korea holds nuclear weapons or the ability to deliver those nuclear weapons to anyone in the region, much less, to the homeland," he said.

The top diplomat acknowledged that the options for dealing with the recalcitrant regime are "limited," especially under a short period of time.

"We're trying to convey to the North Koreans, 'We are not your enemy. We're not your threat, but you are presenting an unacceptable threat to us, and we have to respond,'" he said. "And we hope that, at some point, they will begin to understand that and that we would like to sit and have a dialogue with them about the future that will give them the security they seek and the future economic prosperity for North Korea, but that will then promote economic prosperity throughout Northeast Asia."

The secretary also urged China to do more to rein in Pyongyang.

He noted, however, that the US does not blame China for the North Korean nuclear conundrum and Pyongyang "does not define" Washington's relationship with Beijing.

Alan Romberg, distinguished fellow and director of the East Asia Program at the Stimson Center, said he views the secretary's remarks as an "excellent" statement of where US policy is and ought to be.

"North Korea would do well to test this statement through engaging in serious dialogue that holds denuclearization out as its ultimate goal, meanwhile suspending tests and other activities that lead the United States and others to adopt defensive postures that Pyongyang sees as threatening," he said in an email to Yonhap.

"Given the history of enmity and mistrust, this is no doubt a hard message for the North to accept at face value. But I believe it is sincere and worth the North exploring. (Yonhap)