The exercise is taking place while U.S. President Donald Trump is on an Asian tour and presenting a united front with regional leaders.
The last time such drills were held was during the Valiant Shield exercises in 2006 and 2007, which took place off the coast of the USA territory of Guam, which hosts two US military bases and is on the North Korean radar for a potential missile strike.
According to reports, the exercise will involve seven South Korean and 11 USA ships, as well as the USS Ronald Reagan, Theodore Roosevelt, and Nimitz.
"A touch-and-go situation is prevailing in the peninsula due to the US and south Korean puppet forces' military provocations", the official Rodong Sinmun wrote. He added, "Multiple carrier strike force operations are very complex, and this exercise in the Western Pacific is a strong testament to the U.S. Pacific's ability and ironclad commitment to the continued security and stability of the region".
The country's joint chiefs of staff (JCS) announced Friday that South Korea will send seven of its warships-including two Aegis Combat System-equipped vessels, one destroyer and four frigates-to join three US aircraft carriers deployed in the Western Pacific that will perform their first joint drill in a decade.
The aircraft carrier USS Ronald Reagan conducts joint drills with the South Korean navy at sea on October 19.
According to the U.S. Navy, it is the first three-carrier exercise in the Western Pacific since 2007.
The Navy noted that for more than 70 years, the U.S. Pacific Fleet has been a persistent and stabilizing presence conducting operations throughout the region.
"The strike force plans to conduct air defense drills, sea surveillance, replenishments at sea, defensive air combat training, close-in coordinated maneuvers, and other training", said a statement from the Navy's 7th Fleet, which is responsible for monitoring the Pacific including North Korea.
South Korea's Yonhap news agency described the exercises as an "unprecedented show of force" off the peninsula.
In late May, Reagan and the Carl Vinson Carrier Strike Group conducted the first dual-carrier operations off of the Korean Peninsula since the late 1990s in reaction to a series of provocative missile tests conducted by North Korea.
He said of the North Korean threats to strike the US and its allies, "That would be a fatal miscalculation".