Speaking outside the Bedminster Golf Club in New Jersey, Trump was responding to critics who called his comments excessive.
“Frankly, the people who were questioning that statement, was it too tough? Maybe it wasn’t tough enough,” he said on Thursday.
“It’s about time someone stood up for the people of our country,” he added.
He also said the U.S. military backed his comments 100 per cent.
On Tuesday, Trump’s initial comments were made after reports that North Korea had successfully miniaturized warheads to fit on intercontinental ballistic missiles (ICBM).
“North Korea best not make any more threats to the United States. They will be met with fire and fury like the world has never seen,” Trump told reporters at the time.
WATCH: Jackson Proskow reports on how both countries are preparing to flex their military muscle.
Since then, North Korea’s state media reported on an upcoming plan to attack U.S. territory Guam with four missiles.
When asked about negotiations, Trump said they’ll always consider talks.
“But they’ve been negotiating now for 25 years,” he said. “I talk. Somebody has to do it.”
He also ended with another warning to North Korea and Kim Jong Un, saying they need to “get their act together” or they will be in trouble “like few nations have ever been.”
The United States and South Korea remain technically still at war with North Korea after the 1950-53 Korean conflict ended with a truce, not a peace treaty.
WATCH: Coverage of escalating tensions between the U.S. and North Korea
Tension in the region has risen sharply since the reclusive communist country — which staged two nuclear bomb tests last year — launched two intercontinental ballistic missile tests in July in defiance of world powers. Trump has said he will not allow Pyongyang to develop a nuclear weapon capable of hitting the United States.
North Korea’s army will complete the plans in mid-August to fire four intermediate-range missiles over Japan to land near Guam, when they will be ready for leader Kim Jong Un’s order, state-run KCNA news agency said. The plans called for the missiles to land in the sea 30-40 km (18-25 miles) from Guam.
WATCH: U.S. Secretary of Defence James Mattis emphasizes diplomatic approach against North Korea which he says is gaining traction
Trump also said that new sanctions on North Korea approved by the U.N. Security Council on Aug. 5 that could slash by a third the country’s $3 billion annual export revenue probably “will not be as effective as a lot of people think it can be, unfortunately.” Trump praised China and Russia for backing the sanctions, but pressed Beijing to do more.
*with files from Reuters
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