South Korea said Wednesday a 2015 deal intended to end a festering dispute with Japan over Tokyo’s wartime sex slavery was faulty, reopening a historical wound as the two countries try to rein in North Korea.

Tokyo has withdrawn its ambassador to Seoul after a new statue in honor of “comfort women” is placed outside its Busan consulate. There are also fears that the political turmoil in Seoul would jeopardize the 2015 deal.