SEOUL - South Korea's President Roh Moo-hyun takes a historic step across the heavily armed border with communist North Korea on Tuesday for only their second summit, billed as a chance to bring peace to the divided peninsula.

South Korean officials have made clear that to keep the mood from turning sour in talks with North Korean leader Kim Jong-il, Roh will step lightly round the paranoid state's nuclear weapons programme and widely condemned human rights record.

Roh, with just six months left in office, has said he would use his talks to press for peace and an eventual arms cut for the states -- technically still at war -- and may pledge billions of dollars for the North's beleaguered economy.

He will lead a motorcade from Seoul on Tuesday morning that includes some 200 business leaders, bureaucrats, poets and clerics, stepping out of his bullet-proof limousine to become the first leader from the South to walk across the fortified border that has split the peninsula for over half a century.

He then drives on to Pyongyang, where the states held their first summit in June 2000.

The talks come amid the latest round of negotiations among regional powers to persuade the North to give up nuclear weapons in return for aid. South Korean officials said Roh would urge Kim to stick to his pledges to denuclearise.

Roh has said the top item on his agenda would be establishing greater peace along the Cold War's last frontier.

"It will not be an uneventful course, but once discussions on a peace regime get under way in earnest, we can take up building military confidence and a peace treaty, and furthermore the issue of arms reduction," Roh said on Monday.


U.S. KEY

South Korea's ability to seek a peace treaty is limited because it was not a signatory to the ceasefire that ended the 1950-53 Korean War. U.S.-led forces signed the agreement.

U.S. President George W. Bush has said he is ready to discuss a peace treaty once the reclusive North scraps its atomic arms and so removes one of the region's greatest security threats.

North Korea has stationed most of its 1.2 million-man military near the border with the South, which has about 670,000 troops backed by about 28,000 U.S. troops.

Although South Korea has lived for decades with the military threat, some analysts say its greater fear is that the sudden collapse of Kim's autocratic government would create enough instability to badly damage its economy, Asia's fourth largest.

North Korea's economy has become a shambles under Kim while his neighbour's has surged. Hit hard by U.N. sanctions for its October 2006 nuclear test and massive summer floods, North Korea depends on food and oil handouts.

"South Korea's economic cooperation is aimed at reducing military tension," said Jeong Hyung-gon, an expert at the Korea Institute for International Economic Policy. "A peaceful peninsula has a direct impact on South Korea's economy."

The first summit broke the ice in the two states' Cold War rivalry and launched economic and humanitarian projects.

Officials said Roh might propose new projects to rebuild the North's dilapidated infrastructure and develop joint economic zones in the isolated state where its own dynamic manufacturers could further exploit cheap land and labour.