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President Trump took to Twitter early Wednesday to note the United States’ nuclear arsenal is “stronger than ever before,” hours after issuing a harsh warning that North Korea would face "fire and fury" if it continued to provoke America.

“My first order as President was to renovate and modernize our nuclear arsenal. It is now far stronger and more powerful than ever before,” Trump tweeted Wednesday morning. “Hopefully we will never have to use this power, but there will never be a time that we are not the most powerful nation in the world!”

Trump’s tweets come after his boldly chilling response to reports that North Korea has produced a compact nuclear warhead capable of topping missiles that could reach half of the United States.

While Trump's claim that the U.S. arsenal is more powerful than ever is true, that process began before he took office. The Obama administration consistently pushed for modernizing the nuclear arsenal, beginning with the 2010 treaty with Russia that reduced warhead numbers, but updated firepower.

In Obama’s exit memo, he outlined the importance of ensuring “the security and reliability of our nuclear arsenal” to “refurbish aging weapons.”

At the end of the Obama administration, then-Defense Secretary Ash Carter announced that the Pentagon would spend $108 billion over the next five years to sustain and improve the U.S. nuclear force.

The president is on a “working” vacation from his property in Bedminster, N.J., and said Tuesday afternoon that Kim Jong Un and North Korea “will be met with fire, fury and frankly power, the likes of which the world has never seen before.”

Trump also said that North Korean dictator Kim Jong Un “has been very threatening beyond a normal state” and said the regime “best not make any more threats to the United States.”

The report that Pyongyang has missile-ready nukes, first appearing in the Washington Post, has been confirmed by Fox News. The assessment of North Korea’s nuclear capabilities was prepared in July by the Defense Intelligence Agency (DIA).

“The [intelligence community} assesses North Korea has produced nuclear weapons for ballistic missile delivery, to include delivery by ICBM-class missiles,” an excerpt from the DIA analysis read.

The report also says that Un may control up to 60 nuclear weapons.

TRUMP: NORTH KOREA 'WILL BE MET BY FIRE AND FURY LIKE THE WORLD HAS NEVER SEEN' IF MORE THREATS EMERGE

The DIA report echoed evaluations in a Japanese defense white paper, also revealed Tuesday.

“It is conceivable that North Korea’s nuclear weapons program has already considerably advanced and it is possible that North Korea has already achieved the miniaturization of nuclear weapons into warheads and has acquired nuclear warheads,” Japan’s defense ministry said in the 500-page report.

The North Korean regime has conducted 12 tests so far this year, with one ICBM test conducted in late July sending a missile 2,300 miles into space and 45 minutes into the air. It was the longest, and farthest ballistic missile test in the history of North Korea, officials told Fox News at the time.

HALEY: NORTH KOREA NEEDS TO BRACE FOR COMBINED PRESSURE FROM US AND THE WORLD

North Korea has threatened that the United States would pay dearly “thousands of times” for new sanctions passed over the weekend by the United Nations Security Council to cripple the nation’s economy, but U.S. Ambassador to the U.N. told Fox News that America has the upper hand.

“It was a gut-punch to North Korea, to let them know the international community is tired of it and we’re going to start fighting back,” Haley said on “The Story” earlier this week. “Every dollar of revenue that the North Korean government gets, they’re not feeding their people with it. They’re using it toward a nuclear weapons system. Going after these sanctions is going after their ability to build these missiles.”

Fox News' Wes Barrett and Lucas Tomlinson contributed to this report.