Seoul has allowed the delivery of flour to North Korea, the first food deliveries since the North's deadly shelling of South Korea's Yeonpyeong Island last year.

The delivery by humanitarian groups is happening during the week of the 58th anniversary of the armistice that ended the 1950-53 Korean War but which left the two Koreas technically in a state of war.

The 295 tons of flour carried on 12 trucks are destined for a nursery, a children's hospital and a kindergarten, South Korea's Unification Ministry spokesman Chun Hae-sung said.

Apart from small private deliveries of food to North Korea by several non-government organizations, Seoul has kept the border closed to food aid since 2008.

The deliveries are seen as a sign of a general thaw in hostile relations between the two Koreas, especially since the unprovoked Yeonpyeong island attack in November and, before that, the more deadly attack on a South Korean naval ship.

Pyongyang continues to be unapologetic for its shelling of Yeonpyeong Island that killed four people. But North Korea maintains no involvement in the March 2010 sinking of the Cheonan naval vessel in which 46 sailors died.

South Korean President Lee Myung-bak said this week South Korea will continue to seek "principled dialogue" with North Korea to break the deadlock in their relations, according to a senior presidential aide.

Lee made the comment during a Cabinet meeting, senior presidential spokesman Kim Du-woo told reporters.

Yonhap news agency commented that the Lee's remark appears to mean that South Korea will engage North Korea in talks.

"But genuine reconciliation with the communist nation would be out of question unless Pyongyang takes responsibility for last year's two deadly attacks on the South," Yonhap said.

Even so, this week could see a meeting in New York between a senior North Korean diplomat involved in nuclear negotiations and Stephen Bosworth, the top U.S. envoy on Korean Peninsula affairs.

North Korea's Vice Foreign Minister Kim Kye Gwan was expected in New York Thursday on the invitation of private think tanks. He is also expected to meet with U.S. officials, including Bosworth.

The meeting could be the beginning of more constructive de-denuclearization talks and the restart of stalled six-party talks on the issue. The six countries in the talks are China -- a staunch ally of North Korea -- the two Koreas, Japan, the United States and Russia. The talks were shelved in 2009 when Pyongyang pulled out to protest U.N. sanctions over its nuclear tests.

Despite a perceived thaw in diplomatic relations, military tensions remain high in the peninsula. North Korea reportedly is preparing warships and fighter planes for an all-branches military exercise on its west coast, a South Korean source told Yonhap.

"We noted preparations for a military exercise from the North's naval base in Nampo and its aerial base in Onchon in South Pyongan province," the government source told the news agency while referring to the western province north of the border.

"Warships and fighters have been assembled there. It depends on the weather but we believe they're setting up for a landing exercise sometime after Wednesday."