North Korea reiterated Thursday that its deadly artillery attack on a South Korean border island last November was provoked by Seoul, in a statement which dimmed hopes of an easing of tensions.

Seoul says Pyongyang must accept the blame for the shelling, and for the sinking of a South Korean warship last March, before any high-level talks can be held to improve relations.

Preparatory military talks broke down this month when the North refused to accept responsibility.

An uncompromising 6,300-word statement released by Pyongyang's official news agency made it clear no apology will be forthcoming.

The South, citing a multinational investigation, says a North Korean torpedo sank the Cheonan corvette near the disputed Yellow Sea border with the loss of 46 lives.

The North vehemently denies responsibility, saying the South faked evidence in a bid to escalate confrontation.

It says its shelling of Yeonpyeong island, also near the border, was in response to a South Korean artillery drill on the island which dropped shells into waters claimed by Pyongyang.

"The Yeonpyeong island shelling was a planned provocation aimed to trigger off a direct military clash against the (North) Korean People's Army through a reckless preemptive attack," said the statement from an inspection group of the National Defence Commission, the North's most powerful body.

The shelling killed two marines and two civilians, wrecked or damaged scores of homes and caused outrage in the South.

Thursday's statement reiterated claims the civilians were used as "human shields" and -- unlike a statement last year -- failed to express regret for non-military casualties.

The civilians were "enlisted in the armed forces" and "were in the barracks of the puppet army", it said.

"Had they not entered the barracks, they would not have met death."

The statement accused South Korea's "traitor" President Lee Myung-Bak of scrapping cross-border agreements reached by his predecessors and pursuing confrontation in collusion with the United States.

Washington was seeking world domination and fuelling confrontation in Korea to bolster a tripartite military alliance with Seoul and Tokyo, it said.

The North repeated calls for a realignment of the Yellow Sea border known as the Northern Limit Line, which was drawn unilaterally by US forces after the 1950-53 war.

If Seoul continued to reject dialogue and pursue confrontation, there were fears that "this will entail miserable consequences of swamping the whole land of South Korea as the Cheonan warship and turning it into a wormwood field like Yeonpyeong island".