I don’t see how they could considering the US would likely veto it since the Korean boarder is protected by landmines.
(The 1997 Convention on the Prohibition of the Use, Stockpiling, Production and Transfer of Anti-Personnel Mines and on their Destruction) The 1997 Mine Ban Treaty entered into force on 1 March 1999.
Notice most countries that do not need landmines as a barrier to agression signed the Treaty. South Korea and the USA did not accept this treaty. The USA is hated by the treaty proponents for refusing it yet the proponents would mere "cluck" if South Korea were overrun with the landmines removed. The landmine ban in Afganistan does not stop the terrorist Taliban men from setting IEDs.
Dates are for signature/ratification or accession (a)