President Trump spoke with South Korean President Moon Jae-in on Friday about the North Korean threat and during the call gave "conceptual approval of planned purchases" of military equipment.

As Pyongyang continued its provocations in the region this week, launching a ballistic missile that flew over Japan, a readout from the White House said Trump and Moon discussed their countries' "coordinated response to North Korea's continued destabilizing and escalatory behavior."

"The two leaders agreed to strengthen our alliance through defense cooperation and to strengthen South Korea's defense capabilities," the statement said. Trump at one point in this conversation also "provided his conceptual approval of planned purchases by South Korea of billions of dollars in American military equipment," according to the readout.

The statement didn't go into further detail.

South Korea already has some U.S. THAAD (Terminal High-Altitude Area Defense) batteries deployed, and though he initially opposed further U.S. missile defense buildup, Moon has recently called for more talks about adding more THAAD coverage.

Beyond missile defense, the U.S., South Korea, and Japan showed off their military might in joint excercises this week. A U.S. Navy destroyer in the Pacific used an enhanced missile to shoot down a medium-range ballistic missile target during a test on Tuesday, one day after North Korea test-launched a similar missile -- the one that flew over Japan.

North Korea has conducted a number of missile tests in recent months as part of its nuclear program and has repeatedly threatened the U.S. territory of Guam.

Trump on Wednesday seemed to rule out the possibility of negotiating some kind of truce with North Korea, though members of his administration have indicated otherwise. "The U.S. has been talking to North Korea, and paying them extortion money, for 25 years. Talking is not the answer!" Trump tweeted Wednesday.

Still, the White House readout said both Trump and Moon "pledged to continue to apply strong diplomatic and economic pressure on North Korea and to make all necessary preparations to deter and defend against the growing threat posed by North Korea."