US Secretary of State Rex Tillerson, en route to the Pacific island of Guam, which the Democratic People's Republic of Korea has threatened to attack, appeared to have played down the situation following an exchange of fierce rhetoric by the two countries.

Traveling to Guam on Wednesday after a trip to Asia, Tillerson said, "I do not believe that there is any imminent threat, in my own view.

"Nothing that I have seen, and nothing that I know of would indicate that the situation has dramatically changed in the last 24 hours," he responded when asked if the US was moving toward a military option sooner than anticipated.

The DPRK has warned of pre-emptive strikes against Guam after two US strategic bombers were sent again on Tuesday to the Korean Peninsula to stage mock nuclear bomb droppings on DPRK strategic targets, DPRK's official Korean Central News Agency said on Wednesday.

Guam became a US territory in 1898, and the US maintains a naval and air force base there.

On Tuesday, the KCNA quoted a spokesman of the Strategic Force of the Korean People's Army as saying that DPRK leader Kim Jong-un has "recommended examination of a powerful and effective action plan for containing the US imperialists' aggression hardware, as the US forces are resorting to inappropriate and reckless military actions in the sensitive area".

This came on the same day when US President Donald Trump threatened the DPRK with "fire and fury like the world has never seen" if, he said, the DPRK does not stop making threats with nuclear and missile weapons.

Tillerson said the Americans "should have no concerns about this particular rhetoric of the last few days".

"I think what the president was just reaffirming is the United States has the capability to fully defend itself with any attack, will defend our allies, and we will do so," he said. "So the American people should sleep well at night."

However, US Secretary of Defense Jim Mattis on Wednesday continued to ratchet up the rhetoric, saying, "The DPRK should cease any consideration of actions that would lead to the end of its regime and the destruction of its people."

China urged calm on Wednesday, saying such rhetoric could escalate tensions on the Korean Peninsula.

In a statement, the Chinese Foreign Ministry called on all parties to avoid any words or actions that might escalate tensions and make a greater effort to resolve the issue via talks.

Richard C. Bush, senior fellow of foreign policy at the John L. Thornton China Center of the Brookings Institution, also downplayed the danger from the DPRK.

"But even when -not if - North Korea has the ability to strike the United States, that does not mean it will use that capability against us," Bush said in a blog posted at the Brookings website on Wednesday.

Xinhua contributed to this story.

huanxinzhao@chinadailyusa.com