North Korean defectors fly balloons with anti-Pyongyang messages written on them from near the inter-Korean border in Paju, Gyeonggi Province, in April 2016. Yonhap

The unification ministry on Tuesday announced finalized guidelines on a legislated ban on sending anti-Pyongyang leaflets into North Korea in an effort to ensure better interpretation of the law.

The amendment to the Development of Inter-Korean Relations Act, set to take effect later this month, has raised concerns that it could hurt freedom of expression and undercut efforts to send information into the reclusive North.

Concerns have also been raised that the law could prohibit the sending of leaflets or other items to the North from a third country, such as China, which the ministry has denied.

"To clarify the definition, the guidelines announced today serve to stipulate that the law applies to cases in which items are sent from South Korea to North Korea," a ministry official said.

"That is from the southern side of the military demarcation line to the northern side, and the law does not apply to cases in which items are sent to the North from a third country," the official added.

The ministry finalized the guidelines after receiving public opinions since it was drafted in January.

The law prohibits the launching of anti-Pyongyang leaflets across the border, with violators subject to a maximum prison term of three years or a fine of 30 million won (US$27,400). (Yonhap)