It said the US Forces Korea (USFK) will position the launchers at its new base in Seongju, some 300 kilometres south of Seoul, on Thursday, along with construction equipment and related materials.
Moon also expressed regret over clashes between protesters and police that left dozens injured Thursday when the US military added the four launchers to the Terminal High-Altitude Area Defense System in rural Seongju.
"To the degree that North Korea knows that the global community is going to punish it for conducting its sixth nuclear test - or try to punish it, at any rate - there is no incentive not to do something else provocative on September 9".
Sweden has urged its citizens to refrain from unnecessary trips to North Korea following the country's sixth and most powerful nuclear test to date.
The United States wants the UN Security Council to impose an oil embargo on North Korea, ban its exports of textiles and the hiring of North Korean labourers overseas, and to subject leader Kim Jong Un to an asset freeze and travel ban, according to a draft resolution seen by Reuters on Wednesday. North Korea has continued ratcheting up tensions with a series of provocations since Moon took office.
Several U.S. military vehicles, including trucks carrying payloads covered in black sheets that appeared to be launchers, had been seen heading toward the site.
US President Donald Trump criticized Moon this week for seeking "appeasement" with Pyongyang, while in August, Moon issued a forceful statement rebuking Trump's threats of "fire and fury" against North Korea, saying that any military actions on the Korean Peninsula must be made in consultation and with agreement from Seoul.
The defense ministry said that, despite the protests, the THAAD deployment was completed.
"North Korea could be playing with us, looking like they're moving stuff around just to keep people on edge", Delury said.
"We believe that sanctions and pressure are only half of the key to resolving the nuclear issue".
The mouthpiece of the North's ruling party called for more "miracle-like events" such as the two ICBM tests to deter the United States which it said was bent on "decapitating" the nation's leader.
"The battery will be operational as soon as the U.S. finishes its internal procedures", Ministry spokesperson Moon Sang-gyun said at a press conference, reported Yonhap news agency.
But after North Korea's two test-launches of intercontinental ballistic missiles, he allowed more launchers to be set up before the reviews are conducted.
Moon temporarily halted the THAAD installation for environmental reviews to ease residents' concerns.
Seonju residents and activists have raised worries over rumoured health hazards linked to the system's powerful radar and the possibility the town will become a target of North Korean attacks.