Aug. 21 (UPI) -- A U.S. decision to scale back the number of troops taking part in joint military exercises on the Korean peninsula is unrelated to North Korea tensions, U.S. Defense Secretary James Mattis said.
The statement came a day ahead of U.S.-South Korea war simulation drills, known as Ulchi Freedom Guardian, began on Monday.
According to the U.S. Department of Defense, Mattis told reporters during a flight to Amman, Jordan, that a substantial reduction in troops had been planned months in advance.
Mattis' statement comes after Pyongyang warned of a "second Korean War" should Seoul and Washington go ahead with drills.
"If sparks fly as a result of an incident, no amount of strength could prevent war," North Korea stated.
The U.S. defense secretary also said the decision to reduce troops was made early, and in close consultation with South Korea counterparts.
Last week, the Pentagon stated approximately 17,500 U.S. troops will be taking part in the exercises.
According to South Korean newspaper Hankyoreh, that number is a reduction from 25,000 U.S. troops taking part in Ulchi Freedom Guardian in 2016.
Mattis told reporters Sunday North Korea knows the drills are a defense exercise, and not a rehearsal for an invasion, as claimed by Pyongyang's propaganda.
About 50,000 South Korean troops are joining U.S. troops for this week's exercises.