"We fly in bombers from Guam. I said when I first started, I said, where do the bombers come from? Guam. Nearby. I said, 'Oh great, nearby, where is nearby?' Six and a half hours. Six and a half hours. That's a long time for these big massive planes to be flying to South Korea to practice and then drop bombs all over the place and then go back to Guam," Trump said.

Trump also noted that flying U.S. Air Force bombers in regional training missions is another drain on resources.

"We will be stopping the war games, which will save us a tremendous amount of money," Trump said in his hour-long news conference following the Singapore summit. "The amount of money that we spend on that is incredible," he added.

President Donald Trump promised North Korean leader Kim Jong Un that he would halt U.S.-South Korea military exercises , saying they are "provocative" and "tremendously expensive."

For the last 14 years, the U.S. Air Force's B-1B Lancer, B-52 Stratofortress and B-2 Spirit bombers have continuously rotated through Guam in an effort to show American commitment to allies in the region.

Trump says the bomber flights are "very expensive."

According to estimates that the U.S. Air Force provided CNBC, the B-2 has an operational flight cost of $130,000 an hour and the B-1B operates at $95,000 an hour.

As the U.S. and North Korea negotiate a nuclear deal, "I think it's inappropriate to be having war games," Trump said. "Number one, we save money. A lot. And number two, it really is something that I think they [North Korea] very much appreciated."

Trump's move falls out of step with the Pentagon, which has maintained that the joint exercises are routine, purely defensive and vital to maintaining readiness on the Korean peninsula.

The Pentagon did not immediately respond to CNBC's request for comment.

But retired U.S. Army Lt. Col. Daniel Davis, who served as an advisor to the Second Republic of Korea Army during his military career, noted that suspending drills in North Korea's backyard is not unprecedented.



"As a goodwill gesture, we suspended the drills around the Olympics and that produced positive results that, in part, helped lead to yesterday's summit," Davis, a senior defense fellow for Defense Priorities, told CNBC.

"We give up nothing by suspending these drills, and we don't lose one ounce of military capability. No one said anything about American military stopping their training, South Korea military stopping their training, it's only that the joint drills will be suspended, and suspended means they can be turned back on if conditions change," Davis added.

As of yet, the Pentagon has not updated guidance for U.S. troops slated to participate in the bilateral Ulchi Freedom Guardian exercises later this year.

Ulchi Freedom Guardian, one of the largest military exercises in the world, ran for 11 days last year and involved 17,500 Americans and 50,000 South Korean troops.