North Korea’s new intercontinental ballistic missile (ICBM) represents “a new escalation of the threat to the United States,” Japan and South Korea, the U.S. said, as dictator Kim Jong Un pledged not to give up his isolated country’s burgeoning nuclear weapons capabilities while continuing to dole out “gift packages” of missile and atomic tests.

The United States and the two Asian allies effectively confirmed Wednesday that the launch was indeed of a long-range missile, with U.S. Secretary of State Rex Tillerson urging “global action … to stop a global threat.”

In Tokyo, Chief Cabinet Secretary Yoshihide Suga told a news conference that the missile “was highly likely to be an ICBM,” citing its estimated firing range of more than 5,500 km.

Suga declined to comment on any potential effects the launch could have on the U.S. nuclear umbrella under which Japan is protected.

North Korea said a day earlier that the test was of “a very powerful ICBM that can strike any place in the world,” calling it “a major breakthrough” in the country’s history.

While there was widespread skepticism over the claim of being able to hit targets across the globe, experts said the missile now put Alaska — and possibly even sites further afield — within striking distance.

The state-run Korean Central News Agency reported Wednesday that the launch had also confirmed that the long-range missile was “capable of carrying a large-sized heavy nuclear warhead” and had verified “all technical features of the payload of the rocket during its atmospheric re-entry, including the heat-resisting features and structural safety of the warhead tip.”

Doubts remain about whether the North has mastered the technology needed to mount a small enough nuclear warhead onto the tip of a long-range missile. There are also questions over the North’s ability to build a warhead that could survive the re-entry process into Earth’s atmosphere.

Kim said the successful test had bolstered the isolated country’s strategic weapons capabilities, which he claimed include atomic and hydrogen bombs and long-range missiles, putting the country “on a new level … despite the hostile forces’ persistent pressure and sanctions,” according to KCNA.

The missile, Kim said, was a “gift bundle” for the “Yankee bastards” on the U.S. Independence Day holiday, with the North Korean dictator calling for the country to “frequently send big and small ‘gift packages’ to the Yankees as ever so that they would not feel weary.”

Pyongyang said the missile, a Hwasong-14, flew 933 km, hitting an altitude of 2,802 km with a flight time of 39 minutes. This corresponded roughly with estimates by Japanese and South Korean officials.

David Wright, co-director of the U.S.-based Union of Concerned Scientists, said that if the time and distance are correct, the missile could have a possible maximum range of 6,700 km — which would put Alaska in striking distance of the North if fired at a normal trajectory.

“Technically, an ICBM is considered any missile with a range greater than 5,500 km, so if this range estimate is right, this would be considered an ICBM,” Wright told The Japan Times. “It would still fall short of reaching the lower 48 states, however.”

While the North has been hit by a raft of harsh U.N. sanctions over its nuclear weapons and missile programs, the country has plowed large amounts of cash and manpower into its effort to secure a credible nuclear deterrent against what it views as the threat of U.S. invasion.

Citing the demise of late Libyan leader Moammar Gadhafi and Iraqi dictator Saddam Hussein — who both had nascent nuclear weapons programs but gave them up for security assurances — North Korean experts and even state-run media reports say Kim likely views his atomic arsenal as crucial to ensuring his regime’s survival.

But the U.S. and its allies have maintained that any restart to negotiations toward cooling the heated tensions would hinge on a promise to denuclearize by the North, something Kim has repeatedly ruled out.

The North said it will “neither put its nukes and ballistic rockets on the table of negotiations … unless the U.S. hostile policy and nuclear threat … are definitely terminated,” according to the KCNA report.

In a statement, Tillerson, however, reiterated the U.S. position that Washington “will never accept a nuclear-armed North Korea,” and said that the matter would be discussed at the United Nations Security Council, which was to hold an emergency session Wednesday afternoon, where the top American diplomat said Washington would seek even stronger measures to rein in the ﻿﻿recalcitrant country.

Tillerson also said that any country that hosts North Korean workers, provides economic or military aid to Pyongyang, or fails to implement U.N. sanctions “is aiding and abetting a dangerous regime.

“All nations should publicly demonstrate to North Korea that there are consequences to their pursuit of nuclear weapons,” he said.

U.S. President Donald Trump has pinned much of his administration’s North Korea strategy on China doing more to corral the North, though he has in recent days distanced himself somewhat from this policy.

Trump had said in January that Pyongyang’s quest to develop a nuclear-tipped missile capable of hitting the U.S. would not happen on his watch. After the latest launch, he blasted Kim on Twitter, asking: “Does this guy have anything better to do with his life?”

The U.S. leader also appeared to say in a series of tweets that Tokyo and Seoul had reached the limits of their patience, while also continuing to urge Beijing to heap pressure on Pyongyang.

“Hard to believe that South Korea and Japan will put up with this much longer,” he wrote. “Perhaps China will put a heavy move on North Korea and end this nonsense once and for all!”

But while the White House has pushed a policy of “maximum pressure,” some experts say that more could be done — even without Beijing’s help.

“The Trump administration should shake itself loose from the self-spun spell that it can depend on China to rein North Korea in and ratchet up the sanctions dial,” said Sung-Yoon Lee, a Korea expert at The Fletcher School at Tufts University in the U.S. “Contrary to the popular notion that U.S. sanctions against North Korea are maxed out, they are not nearly as tough as past and present U.S. sanctions against many other nations, including Iran, Syria, Myanmar, Cuba, Zimbabwe, Belarus.”

A June report by the London-based Royal United Services Institute think tank focusing on the challenges of implementing the sanctions backed up Lee’s claims, noting that “not a single component of the U.N. sanctions regime against North Korea currently enjoys robust international implementation.”

First and foremost, Lee said Washington could do more “to constrict Pyongyang’s money flow directly and indirectly by imposing financial costs on Chinese partners.

“The Trump administration should, as the old Nike commercial went, ‘Just do it.’ “

But Lee said “the same old story of North Korean provocations, return to negotiations, and reaping concessions will continue for now,” while also urging Japan “to stay the course and not relax sanctions as its neighbors, South Korea and China, merely go through the motions.”

As for Trump’s other options, and how the new missile could affect Japan and South Korea, experts and former diplomats were more sanguine.

“Our allies have been living under the threat of North Korean missiles for years,” said Abraham Denmark, former U.S. deputy assistant secretary of defense for East Asia until January. “This only affects our allies in that they fear it could change the calculus in Washington.”

Trump, however, has been known to favor shaking up that very same calculus, including earlier talk — since walked back — of a regional pullout and a nuclear-armed Japan and South Korea.

Euan Graham, director of the International Security Program at the Lowy Institute in Sydney, said that while it remains too early for the ICBM to impact extended deterrence, “both allies are already thinking about their defense in more independent terms.”

Graham said that “for Japan, it will sharpen the debate about conventional strike capability,” including on acquiring cruise missiles and precision munitions for its new F-35 fighter jets.

“Japan will only go nuclear if their territory is directly threatened,” he said, adding that Tokyo would not go down that road “as long as the U.S. alliance remains in place.”

The Pentagon has attempted to assuage such fears, condemning the launch Wednesday and reiterating that the U.S. “commitment to the defense of our allies … remains ironclad.”

The North Korean issue is also expected to be one of the top agenda items at this week’s Group of 20 summit in Germany, where Prime Minister Shinzo Abe was to meet his American and South Korean counterparts for trilateral talks.

Trump, meanwhile, is due to meet both Chinese President Xi Jinping and Russian President Vladimir Putin at the G-20 summit. Abe has said that he will ask the presidents of China and Russia to play more constructive roles.

North Korea was a major topic in phone calls between Trump and the leaders of China and Japan earlier this week.