SEOUL North Korea warned South Korea's new president to "watch her tongue" on Wednesday, as tension between the two sides mounts, reprising the kind of vitriolic language that it dished out to her predecessor on a regular basis.
North Korea has in recent days threatened the United States with nuclear war and rehearsed drone attacks on South Korea, prompting Washington, involved in military drills with the South, to say it is ready for any contingency.
Park Geun-hye, South Korea's first female president, marked the third anniversary of the sinking of a South Korean warship that killed 46 sailors by calling on the impoverished North to abandon its nuclear ambitions to save its starving people.
The South, backed by an international commission, blames a North Korean torpedo attack for the sinking although Pyongyang denies it was responsible.
"The owner of Cheongwadae (South Korea's presidential office) had better... watch her tongue," North Korea's official KCNA news agency quoted a spokesman for the Committee for the Peaceful Reunification of Korea as saying.
North Korea has made no secret of its hatred for Park and earlier this month referred to the "venomous swish" of her skirt.
Tension between the two Koreas has risen sharply since the North conducted its third nuclear test in February, just days before Park took office, in a move that triggered new sanctions against Pyongyang.
North Korea regularly attacked Park's predecessor, Lee Myung-bak, with bellicose rhetoric. It referred to Lee, who cut off aid to Pyongyang during his five years in office, as a "rat-bastard" and shot and hanged him in effigy.
Park, 61, put the building of a new relationship with Pyongyang at the centre of her 2012 election campaign, but has always said that any improvement in relations depended on the North giving up nuclear weapons.
North and South Korea are still technically at war after their 1950-53 civil conflict ended with an armistice, not a treaty, which the North has since said it has torn to pieces.
(Reporting by Ju-min Park; Editing by Nick Macfie)