Mattis noted that North Korean leader Kim Jong Un committed to doing so in his June 12 meeting with President Donald Trump on denuclearising the Korean peninsula.
Kim has also stepped up attacks on capitalism, letting North Koreans know that while he's opening up diplomatic ties, he's not giving up socialism. "We hope that we will have an ongoing process of making progress".
News reports are also addressing President Trump differently, calling him by his title and full name instead of just his last name which is how United States officials are traditionally referenced by the regime's media.
Mattis, at the start of a week-long trip that includes stops in China, South Korea and Japan, said Trump's guidance on suspending military drills applied not just to the major Freedom Guardian exercise in August but also to two smaller Korean Marine Exchange Program training exercises.
Mike Pompeo, the U.S. secretary of state, said he wanted to see continued progress towards North Korean denuclearisation and that the administration would regularly assess Pyongyang's seriousness about abandoning its nuclear program.
"It's remarkable", said Peter Ward, a North Korea researcher at Seoul National University.
A 42-minute documentary-style news special was aired on the state television network two days after the summit and has been repeated frequently since, meaning that by now there are probably few North Koreans who are unaware of the changes in the air.
In a statement, a U.D. official said the timeline will clarify what the implementation of the summit agreement should look like.
On Monday, Pentagon spokeswoman Dana White walked those comments back in a pair of tweets.
More than 36,500 U.S. troops died in the war, and about 7,700 military personnel remain unaccounted for.
During the summit, Kim reaffirmed a commitment toward complete denuclearization of the Korean peninsula, while Trump said he would halt joint US-South Korean "war games."
Less than two weeks after the summit, Pompeo suggested it was too soon to expect a detailed roadmap after 40 years of tensions between the two countries.
The North Korean regime continues its campaign to present leader Kim Jong-un as an approachable modern statesman, with an attractive wife on his arm and other photogenic trappings.
"I will say that there are understandings that have been put together prior to the summit, some that took place when the president was in Singapore that I think put us on the right trajectory so that we can build out a framework for success", Pompeo said. "We have a great chairman, Kim, we have great chemistry".
Pompeo, who has been charged with leading negotiations aimed at persuading North Korea to give up a nuclear weapons program that threatens the U.S., said he would "constantly reassess" whether enough progress was being made to continue talks.