Naval Mobile Construction Battalion 5 sailors and South Korean sailors listen to a briefing as part of the Foal Eagle exercise in Jinhae, South Korea, on March 13, 2017.

Naval Mobile Construction Battalion 5 sailors and South Korean sailors listen to a briefing as part of the Foal Eagle exercise in Jinhae, South Korea, on March 13, 2017. (TORREY W. LEE/U.S. Navy)

SEOUL, South Korea – President Donald Trump warned that he could “instantly” restart war games with South Korea, stepping up pressure on the North amid growing doubts over its willingness to give up nuclear weapons.

Trump also reiterated his allegation that China is trying to sabotage the nuclear talks “because of our major trade disputes.”

The U.S. administration has expressed increasing frustration over the lack of progress in talks nearly three months after Trump and North Korean leader Kim Jong Un met in a breakthrough summit in Singapore.

“There is no reason at this time to be spending large amounts of money on joint U.S.-South Korea war games,” Trump wrote Wednesday in a series of tweets.

“Besides, the President can instantly start the joint exercises again with South Korea, and Japan, if he so chooses,” he added. “If he does, they will be far bigger than ever before.”

Trump and Kim agreed to try to “completely denuclearize the Korean Peninsula” but included no specific measures or timelines for doing so.

The president also announced after the June 12 summit that he was suspending annual military exercises with South Korea, saying they’re very expensive and “provocative.”

Many experts criticized the decision, saying the president was giving up too much without getting major concessions in return.

The exercises have long infuriated North Korea, which sees them as a rehearsal for an invasion.

The move had the immediate impact of canceling the Ulchi Freedom Guardian exercise, which had been due to be held in late August. The Marines also suspended smaller-level drills with South Korea.

The next major exercises on the traditional calendar would be Key Resolve/Foal Eagle, which usually happen in the spring.

Military officials and others say the exercises with U.S. allies South Korea and Japan are crucial to maintaining readiness against a growing threat from the North.

Trump's comments came a day after Defense Secretary Jim Mattis said the Pentagon had “no plans at this time to suspend any more exercises.”

Trump tempered his warning with praise for his relationship with Kim, saying it’s “a very good and warm one.”

The administration has long said a key reason that the North agreed to come to the table after months of missile and nuclear tests was pressure from China, which accounts for 90 percent of trade with Pyongyang.

Beijing agreed to step up its implementation of U.N. sanctions last year, halting coal and other major exports as tensions last year prompted fears of another war on the divided peninsula.

Trump accused China of providing “considerable aid,” including money, fuel, fertilizer and other commodities to the North to undermine U.S. efforts to persuade the smaller communist state to abandon its nuclear weapons program.

“President Donald J. Trump feels strongly that North Korea is under tremendous pressure from China because of our major trade disputes with the Chinese Government,” he wrote. “This is not helpful!”

He tempered the criticism by saying the differences would be “resolved in time” and the two countries maintained a strong bond.

China denied a similar claim by the president last week, saying it was “irresponsible” and not based on facts. Twitter: @kimgamel

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