North Korea said on Wednesday that it would close its land border with the South from December 1, accusing its neighbor of taking confrontation "beyond the danger level."The move follows growing irritation in Pyongyang with the South's conservative government that has promised to get tough with the North if it did not end its nuclear weapons program. It was not clear whether the ban would include blocking access to the Kaesong industrial park, operated by the South just across the border and the one tangible commercial link between the two states which have never agreed a peace treaty to formally end the 1950-53 Korean War. "We officially inform the south side that the actual crucial measure taken by the KPA (North Korean army) to strictly restrict and cut off all the overland passages through the Military Demarcation Line will take effect from December 1," North Korea's KCNA news agency said. "The south Korean puppet authorities should never forget that the present inter-Korean relations are at the crucial crossroads of existence and total severance."There are only two main road crossings over the demilitarisdemilitarizeded zone (DMZ) that has divided the Korean peninsula since 1953. One is to the factory park and on to Kaesong city which has been open to tours for foreigners for almost a year. The other is on the east side of the peninsula to another tour site, Mt Kumgang but which was closed to tourists earlier this year South Korean officials contacted by Reuters said they were checking the KCNA report. Last month North Korea threatened to reduce the South to rubble unless it stopped its civic groups from sending anti-Pyongyang leaflets into the communist state. It is likely to be further irritated by South Korea's human rights agency's decision, announced on Tuesday, to set up a committee to look at abuses in the North. Relations between the states have increasingly frayed since February when conservative President Lee Myung-bak took office pledging to get tough with Pyongyang but offering massive economic aid if it mended its ways. Under liberal presidents over the past 10 years, South Korea has walked on egg shells when it came to human rights, feeling that open criticism of its communist neighbor would derail their plans to draw the North closer through engagement. But conservatives, who argue human rights represent universal values, have said pressing North Korea now cannot harm a relationship that has severely soured. The latest escalation in tension comes amid widespread speculation that leader Kim Jong-il may have suffered from a serious stroke, though the North has insisted he is in good health and still firmly in charge.