President Trump said Sunday "we'll see" if he plans to attack North Korea.
Trump made the remark in response to a shouted question from a reporter as he departed St. John's Church, an Episcopal congregation near the White House.
Trump issued a series of tweets Sunday morning about North Korea after the dictatorship conducted its sixth and most powerful nuclear weapon test.
"North Korea has conducted a major Nuclear Test. Their words and actions continue to be very hostile and dangerous to the United States," he tweeted.
He added: "North Korea is a rogue nation which has become a great threat and embarrassment to China, which is trying to help but with little success."
In a third tweet, he wrote: "South Korea is finding, as I have told them, that their talk of appeasement with North Korea will not work, they only understand one thing!"
Trump warned North Korea last month it would face "fire and fury" in response to provocations, saying explicitly he considered military action an option.
Senior Trump advisor Steve Bannon left the White House last month after saying in an interview with a liberal publication "there's no military solution."
Shortly before Trump's remark, Texas Republican Sen. Ted Cruz said Sunday "no rational person" would want war with North Korea and that "the president speaks in ways I wouldn't speak."