Updated 12:28 p.m. | Democratic lawmakers said Thursday that President Donald Trump canceled a summit with North Korean leader Kim Jong Un because his administration was ill-prepared for the sensitive talks, but GOP members hailed the move as strategically prudent.

A few hours after the White House released a letter he penned to Kim informing him the talks are off — for now, at least — Trump delivered a hawkish warning to the North Korean dictator. The U.S. commander in chief said his military is “ready” and “by far” the most powerful in the world, contending it has been “greatly enhanced.”

“Hopefully positive things will be taking place” with the North, he said. “But if they don’t, we are more ready than we have ever been before.”

House Intelligence ranking member Adam B. Schiff of California blamed the summit’s cancelation on “a poor negotiating strategy in which the president made it all too clear to North Korea that he needed the summit more than the North Korean dictator,” adding in a statement that “this put the United States in a weak bargaining position.”

Earlier, Senate Foreign Relations Chairman Bob Corker signaled he was not disappointed with Trump’s decision to cancel the summit.

“We need to make sure that when we have the meeting, it’s going to be something that’s productive,” Corker said.

Like Corker, other congressional Republicans were quick to applaud the president’s decision.

Trump ally Sen. Tom Cotton of Arkansas, a member of the Armed Services and Intelligence committees, said in a statement that “North Korea has a long history of demanding concessions merely to negotiate.”

“While past administrations of both parties have fallen for this ruse, I commend the president for seeing through Kim Jong Un’s fraud,” Cotton said. “As I have long said, our maximum-pressure campaign on North Korea must continue.”

Sen. Cory Gardner of Colorado, chairman of a Foreign Relations subcommittee that oversees South Asia policy, said in a statement that Trump “has made the right decision to cancel the summit … until North Korea is ready to act in good faith to fully denuclearize,” adding the U.S. “must double down on our strategy of maximum pressure and engagement.”

During a Senate Foreign Relations hearing with Secretary of State Mike Pompeo, ranking member Robert Menendez of New Jersey was skeptical of how the Trump administration handled the run-up to canceling the summit and its surprise at the recent North Korean rhetoric.

“The art of diplomacy is a lot harder than the ‘Art of the Deal,’” Menendez said, referencing the president’s best-selling 1987 book on business. “And the reality is that it’s pretty amazing that the administration might be shocked that North Korea is acting the way North Korea might very well normally act.”

Pompeo rejected accusations the summit fell apart due to a lack of preparation on the U.S. side.

“I think the American team is fully prepared. I think we are rockin’. I think we are ready,” he told the panel. “I think President Trump was ready. We were fully engaged over the last few weeks.”

Pompeo said he met with the Chinese foreign minister yesterday and received from him a commitment that China would maintain all U.N. Security Council sanctions against North Korea.

“The global pressure campaign that has been put in place needs to continue. That is very important so we can ultimately get to the right place,” the secretary said.

Menendez criticized Trump administration officials’ constant references to the “Libya model,” given the North Korean government’s apparent fear of being ousted from power. The New Jersey Democrat also questioned whether the president and his team had conducted any deep preparation for direct talks with Kim.

National security adviser John Bolton had floated the Libya model as what Trump and his team were following as they prepared to talk to Kim. But that raised alarms in Pyongyang, because the United States ultimately supported the movement that led to the ouster and death of former Libyan leader Muammar Gaddafi.

House Foreign Affairs Chairman Ed Royce of California struck a notably less hawkish tone than did Trump. “Our goal is to peacefully end North Korea’s nuclear threats,” he said in a statement. “The administration should continue to look for opportunities while applying maximum diplomatic and financial pressure against Kim Jong Un.”

Speaker Paul D. Ryan also mentioned a peaceful resolution. “The North Korean regime has long given ample reason to question its commitment to stability,” he said Thursday. “We must continue to work with our allies toward a peaceful resolution, but that will require a much greater degree of seriousness from the Kim regime.”

Senate Minority Leader Charles E. Schumer used part of his opening floor remarks to say many in his party feared the summit would amount to “a great show that produced nothing enduring.” He said any new try at talks must start with the Trump administration focused on a “concrete, verifiable, enduring elimination of Kim Jong Un’s nuclear capabilities.”

Seemingly out of the blue, the White House on Thursday morning released Trump’s letter to Kim via an email blast as a senior White House official was briefing reporters on a commercial space policy directive on a conference call.

Trump pinned his decision on Kim’s “tremendous anger and open hostility” in a recent statement, according to a letter released by the White House.

The president used the letter to send a new warning to the North Korean dictator: “You talk about your nuclear capabilities, but ours are so massive and powerful that I pray to God they will never have to be used.”

He did the same during remarks at the start of a bill-signing event at the White House around midday. Trump announced he has spoken to the leaders of South Korea and Japan, saying they have agreed to foot a large portion of the bill if U.S. military operations, “if such an unfortunate situation is forced upon us.”

But, at the same time, in both the letter and his remarks, the president continued to leave open the possibility of one day talking with Kim.

“A lot of things can happen, including … a summit at some later date,” the president said. “No one should be anxious. We have to get it right.”

Despite his atomic warning in the letter, Trump wrote to Kim he is still open to direct talks about a nuclear disarmament pact.

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“If you change your mind having to do with this most important summit, please do not hesitate to call me or write,” he wrote. “The world, and North Korea in particular, has lost a great opportunity for lasting peace and great prosperity and wealth.”

Trump called the failed summit a “truly sad moment in history.”

The North in recent days had lashed out at senior Trump administration officials. Its vice foreign minister criticized officials like Vice President Mike Pence and Bolton, questioning their sincerity ahead of the now-scuttled talks.

A senior North Korean official, Choe Son-hui, on Thursday referred to Pence as a “political dummy” for his comments about North Korea possibly ending up like Libya. Even though Trump this week tried to assure Kim he would be protected after any deal, North Korean officials showed their concern about Trump administration officials’ mentions of Libya.

In one of two statements issued on May 16, the North’s vice foreign minister, Kim Kye Gwan, urged Trump and his administration to approach the summit with “sincerity,” saying only that the approach would have been met with “a deserved response from us.”

“However, if the U.S. is trying to drive us into a corner to force our unilateral nuclear abandonment, we will no longer be interested in such dialogue and cannot but reconsider our proceeding to the DPRK-U.S. summit,” he said.

In another forum, the vice foreign minister attacked Bolton, saying, “We do not hide our feeling of repugnance toward him.”

After senior South Korean officials delivered an invitation from Kim to Washington on March 8, Trump accepted on the spot. The move shocked his top aides and U.S. lawmakers, with even typically critical Democrats giving him credit for getting further with a North Korean leader than previous American commanders in chief.

Such a meeting would have been the first between an American president and a North Korean leader.

Other topics about which the GOP president speaks a lot in public —immigration, the economy, and trade and tax cuts, among others — are sure to be part of Trump’s midterm campaign message to voters.

But one GOP strategist doubts a failed Kim summit — should a meeting not happen before Election Day in November — will help decide which party controls the House and Senate.

“Polling indicates voters give him a lot of credit for getting this far,” the GOP strategist said. “I don’t see evidence of a punishment on something that everyone agrees was always going to be a really hard thing just to make happen, let alone leave with a deal.” 

Rachel Oswald contributed to this report.