Seoul's recent decision to deploy an advanced U.S. anti-missile system in South Korea was triggered by North Korea's increasing nuclear ambitions, the unification ministry said Monday, amid the North's continued bashing of the deployment plan.

North Korea has stepped up its criticisms against the South after July 8 when the plan was announced to allow the Terminal High-Altitude Area Defense system in the country by 2017.

The move is aimed at better defending South Korea from evolving nuclear and missile threats.

"We strongly advise Pyongyang to bear in mind the fact that its ambitions for nuclear weapons and ballistic missiles led to the THAAD deployment decision," Park Soo-jin, spokeswoman for the Ministry of Unification, said in a press briefing.

She warned against the North's "unilateral and distorted" verbal attacks through its state-run Korean Central News Agency and other propaganda channels on the planned THAAD deployment. The official such actions have escalated internal division within the country over those that support THAAD's deployment and those that are opposed to such a move.

In a English statement released on Sunday, the Central Committee of the Union of Agricultural Workers of Korea said, "If THAAD is deployed in Seongju, life, security and livelihood of not only many people in its township amounting to more than half of the county population but also peasants in the area will be exposed to grave danger and its ensuing economic losses will be enormous."

As of the end of June, the number of Seongju residents reached 45,065, according to Seongju County homepage.

On July 13, the Seoul government announced a THAAD battery will be stationed in the county 296 kilometers southeast of Seoul, inviting anger among the residents over possible health risks.

The government has tested the levels of electromagnetic waves emanating from the Patriot PAC-2 and Green Pine systems in Korea and a THAAD system in Guam to help allay health concerns among the residents.

The test results showed that radio waves from all of the three antimissile systems do not pose health risks. But local residents have not accepted the results, raising the possibility that radar waves in the Guam THAAD battery were not gauged when the system was in full operation. (Yonhap)