South Korea's military are securing three Christmas tree towers near the border with North Korea after Pyongyang warned Seoul on Sunday not to light these up.

Christian groups are once again lighting up the Christmas trees on top the Aegibong hill 3 kilometres from the western border with North Korea and south of the demilitarized zone after the tradition was suspended in 2004 as part of a reconciliation South Korea's Defence Ministry has allowed the groups to light the trees on Dec, 23 as they did last year in observance of the Christmas season.

North Korea regard the lighting of the Christmas trees as a form of psychological warfare and its propaganda website Uriminzokkiri warned of "unpredictable situation" if these are lit.

One of the Christmas trees stand 30 metres tall and has 100,000 lights. It can be seen from the North Korean city of Kaesong.

Relations between the two Koreas are tense since the North allegedly torpedoed and sank a South Korean ship and fired artillery shells at a South Korean island that killed 50 South Koreans last year. Before the Christmas tree was lit up last year, North Korea threatened to fire artillery on any place of propaganda activity in the South.

Tak Sejin, chairman of the Yoido Full Gospel Church's military evangelical committee, defended the lighting of the trees.

"This is a lightning ceremony for peace on the Korean peninsula and national unity. It is being held with our desire for harmony among our fellow men, and between North and South Korea We are doing this with the expectation that someday ... our people can become one," said Tak, according to Stars and Stripes.

Tak added that lighting up the Christmas tree until Jan. 6 is not a propaganda but a way to share the spirit of Christmas.
North and South Korea are technically in a state of war as they did not sign a peace treaty after the end of the Korean War. The war ended in an armistice instead.