The Songdo international business district in Incheon is tipped as the likeliest location for a UN field office monitoring human rights in North Korea.
But activists say the office should be in Seoul itself for the sake of convenience and as a symbolic gesture.
Back in February, the UN Commission of Inquiry on Human Rights in North Korea published a report saying that human rights violations in the North constitute crimes against humanity and calling for measures to bring the North Korean leadership to justice.
It also called for a field office to probe human rights abuses in the North.
The UN High Commissioner for Human Rights asked Seoul to host the office, and Seoul decided to open it by the end of the year.