US Secretary of State Rex Tillerson on Sunday ruled out a regime change as its North Korea policy goal, in an apparent message to Pyongyang following a summit with China and military strike in Syria.

“In terms of North Korea, we have been very clear that our objective is a denuclearized Korean Peninsula,” he said in an interview with ABC’s “This Week.”

“We have no objective to change the regime in North Korea -- that is not our objective. And so the whole reasons underlying the development of a nuclear program in North Korea are simply not credible.”

North Korea has been decrying South Korea-US joint military drills and efforts to intensify sanctions and pressure as a plot to topple its regime in line with what it calls a “hostile policy.”

In recent years, the allies have been scaling up the exercises with the participation of top US strategic assets and special forces tasked with eliminating the North Korean leadership in an emergency.

Then the US’ strike in Syria in the middle of a summit between President Donald Trump and his Chinese counterpart Xi Jinping last Thursday fueled speculation that could be a veiled warning to Pyongyang.

On Sunday, the US Pacific Command ordered a strike group to return to waters off the Korean Peninsula, citing North Korea’s “reckless, irresponsible, and destabilizing program of missile tests and pursuit of a nuclear weapons capability.” The group, led by the USS Carl Vinson aircraft carrier, took part in a military drill here last week and was going to Australia from Singapore.

“I think the message that any nation can take (from the Syria attack) is if you violate international norms, if you violate international agreements, if you fail to live up to commitments, if you become a threat to others, at some point a response is likely to be undertaken,” Tillerson said.

National Security Adviser H.R. McMaster, speaking on “Fox News Sunday,” called the diversion of the strike group a “prudent” move, saying Trump has asked for a “full range of options to remove” the North’s threats.

“North Korea has been engaged in a pattern of provocative behavior. This is a rogue regime that is now a nuclear-capable regime,” McMaster said.

Though they did not hold a joint news conference nor release a joint statement, Trump and Xi discussed a “full range of options” on North Korea during the summit, including through one-on-one talks, Tillerson said.

With Beijing calling for dialogue to defuse tension, the secretary also signaled a halt in nuclear and missile tests as a possible step before a restart of talks, calling for a greater Chinese role in fostering the right conditions.

“(We) have called on the government on China to take additional steps. We expect that they will. They have indicated that they will. And I think we need to allow them time to take actions,” he said.

“So what we would hope is that with no further testing, obviously their program doesn’t progress. And that’s what we have asked for, is for them to cease all this testing before we can begin to think about having further talks with them.”

In particular, his unprecedented reference to the regime change could be part of a joint action plan the sides may have agreed on, or the US’ efforts to encourage China to do more to change the Kim Jong-un regime’s thinking, a senior Seoul official said.

“I have no information on the summit, but the remarks seemed to be a message intended to follow up on what’s agreed on during the meeting, and to strengthen China’s hand in setting it in motion,” the official said, requesting anonymity due to the sensitivity of the matter.

“To induce Pyongyang’s attitude toward denuclearization, I believe there will need to be assurances on regime security -- that we have no intention to overthrow the regime -- not by word but through some kind of mechanism.”

In another development, Wu Dawei, special representative for Korean Peninsula affairs at Beijing’s Foreign Ministry, arrived in Seoul on Monday and met with his counterpart Kim Hong-kyun, special representative for Korean Peninsula peace and security affairs at the Foreign Ministry here.

They were expected to discuss the Trump-Xi summit and future steps, and explore the possibility for another major provocation ahead of key national holidays, including a party congress on Tuesday, the 105th birthday of late founding father Kim Il-sung on Saturday and the anniversary of the military’s establishment on April 25.

Pyongyang has been carrying out a string of missile and engine tests in recent months, with satellite imagery suggesting preparations for a fresh nuclear experiment. Last week, it fired another ballistic missile into the East Sea, though it appears to have failed.

“We’ve agreed to take additional strong action if the North conducts a new nuclear or intercontinental ballistic missile test,” Kim Hong-kyun told reporters after the meeting, reaffirming their commitment to continue ramping up sanctions and pressure against the regime.

Wu declined to comment on reporters’ questions.

During his stay here until later this week, Wu is also likely to visit leading South Korean presidential candidates to discuss North Korea policy and China’s opposition to the ongoing deployment here of the US’ Terminal High Altitude Area Defense anti-missile system.

By Shin Hyon-hee (heeshin@heraldcorp.com)