South Korean President Lee Myung-Bak on Wednesday described as "inevitable" the peaceful reunification of his country with North Korea, whose new leader has been in place for nine months.

"We are the only divided nation in the world and it is inevitable that we (will) come to peaceful reunification at some point," Lee told reporters in Oslo.

"Nuclear weapons or military might is not a way for North Korea to overcome the current problem," he said, urging Pyongyang to renounce its nuclear programme as demanded by the United Nations.

The two Koreas have remained technically at war since the Korean War ended in 1953 with a truce rather than a peace treaty.

The death on December 17 of North Korean leader Kim Jong-Il and his replacement by his son Kim Jong-Un have relaunched debate in South Korea about the chances of reunification, though it is seen as being far off given the persisting tension between the two countries.

Last month, Seoul announced the creation of a fund for a potential reunification, with estimates predicting it could cost up to 249 trillion won (171 billion euros, $221 billion) -- almost one-quarter of the South's 2010 national economic output -- for the first year alone if medical costs, pensions and other benefits were factored in.

The astronomical sums have dampened the South Korean public's enthusiasm, as North Korea has indicated that no reforms would be forthcoming.

Lee also discussed his country's ambitions in the Arctic, as Seoul eyes the opening of new shipping routes.

With the Arctic ice cap melting due to global warming, shipping routes between Asia and Europe can be shortened by 40 percent by sailing through the Arctic's so-called Northern Sea Route from the Pacific.

"We need to strike a balance (between) combatting global warming and at the same time preparing ourselves for the new opportunities that will be related to it," Lee said.

The South Korean leader said he was "shocked" to see the rate at which the ice was melting during a visit to Greenland just before his trip to Oslo.

Norwegian Prime Minister Jens Stoltenberg meanwhile reiterated his support for South Korea's observer status on the Arctic Council, an inter-governmental body made up of the countries bordering the region.