north koreahas also in recent weeks alternated between threatening the south and offering apparent concessions.
the two nations remain technically at war because the1950-53 korean war ended in an armistice, not a place deal.
on monday pyongyang offered to suspend hostile military activities and slander, a move seoul descibed as "nonsensical".
north korea has made similar offers in the past but these have invariably broken down.
north korea is also currently engaged in talks with japan on the issue of japannese nationals it abducted in the 1970s and 1980s to teach language andculture to its spies.
japan criticised sunday's rocket launch at the start of one-day talks in beijing on tuesday, at which no breakthorughs were reported.