The Los Angeles Times says North Korea's decision to heavily restrict border traffic with South Korea will further isolate what it called "leader Kim Jong Il's mysterious and reclusive state."

The daily cited analysts as saying the border rift "is the most serious incident in years and highlights deteriorating relations between the two Koreas, whose recent economic overtures had rekindled hopes for reunification after decades of brinkmanship."

It said that tensions rose in February after the election of conservative South Korean President Lee Myung-bak, a hard-liner on Pyongyang and also in August due to public speculation in the South that Kim Jong-il was weakened from a stroke. Seoul also continues to allow defectors to send political leaflets north via balloon.

The report said that analysts believe Pyongyang's move is also directed at the incoming administration of President-elect Barack Obama, sending a message that North Korea is not a nation to be taken lightly.

Analysts say the North seeks to humiliate its neighbor by closing a lucrative South Korean-run industrial park, widely viewed as a symbolic victory for capitalism.