SEOUL (AFP) - South Korea and the US postponed a major military meeting due to take place in Washington, an official said on Sunday as Seoul was on high alert for potential attacks from North Korea.

General Martin Dempsey, chairman of the US Joint Chiefs of Staff, and his Seoul counterpart General Jung Seung-Jo were to coordinate policy on the North and other issues during the annual Military Committee Meeting on April 16.

But the meeting between the two allies had been delayed at Seoul's request, a spokesman for Seoul's Joint Chiefs of Staff said.

"The decision to delay the meeting has been made... due to the current particular situation of our national defence," he said without elaborating.

The request was made Saturday amid concerns that the North may stage a military provocation while Seoul's military chief was away, Yonhap news agency said, citing the South's army official.

Tensions have been running high on the peninsula after a recent series of apocalyptic threats from the North incensed by fresh UN sanctions imposed after its widely-condemned long-range rocket launch and a third nuclear test.

The impoverished but nuclear-armed state has approved a nuclear attack on its "sworn enemy" the US and slapped a rare ban on South Koreans' entry to a Seoul-funded joint industrial complex in the North.

It has also reportedly loaded two intermediate-range missiles on mobile launchers and hidden them near its east coast, fuelling fear of an imminent launch that may further escalate tensions.

North Korea also also gave an evacuation advisory to some foreign embassies in the capital Pyongyang, warning it could not guarantee their safety after April 10 if a conflict broke out, although most appeared to be staying put.