North Korea has made an insulting attack on South Korean President Park Geun-hye, following her recent comments on its nuclear programme.
A spokesman accused her of "blabbering" like a peasant woman and described her as a "faithful servant and stooge of the United States".
Ms Park had warned on Monday that North Korean nuclear devices could end up in the hands of militants.
The North's statement said she must learn to stop reckless talk.
North Korea test-fired two ballistic missiles on Wednesday, an apparent response to the meeting at the Hague between Ms Park, US President Barack Obama and Japanese Prime Minister Shinzo Abe.
They pledged co-operation in the face of North Korea's nuclear and missile programmes.
United States and South Korean forces are continuing annual exercises on and around the Korean peninsula with the largest-scale amphibious landing by US marines in decades.
North Korea has made insulting comments about Ms Park's gender in the past with references to "the venomous swish of her skirt".
But the two states had agreed at a rare high-level meeting last month to end cross-border slander.
North Korea's official Committee for the Peaceful Reunification of the Fatherland said the South Korean leader had violated that agreement during a speech at the nuclear summit in the Hague.
Ms Park had called for an end to North Korea's nuclear programme, expressing fears that nuclear material could be acquired by extremists or cause an accident worse than Chernobyl.
The South Korean government said the North's comments were deeply regrettable and lacking in the most basic etiquette.