South Korea has offered huge amounts of free electricity to North Korea as an incentive to end its nuclear ambitions.
North Korea badly needs more fuel
Seoul is proposing to lay power lines across the Korean border, as an alternative to a US-brokered nuclear power deal which collapsed in 2002.
The offer came as diplomats prepared to resume six-nation talks on the North's nuclear programme later this month.
Earlier, South Korea said it was sending the North 500,000 metric tons of rice to help avert a food crisis.
South Korean Unification Minister Chung Dong-young told a news conference that the power proposal would supply the same amount of electricity that the North would have received if two light-water reactors being built by an international consortium in the 1990s had been completed.
N KOREA'S ENERGY DEALS
N Korea agreed to mothball its nuclear reactors in a 1994 deal
In return, it was to receive two 1,000MW light-water reactors
Deal collapsed in 2002 over enriched uranium programme
The North later restarted its Yongbyon reactor
S Korea now offering 2,000MW of electricity aid
That deal, known as the Agreed Framework, collapsed after Pyongyang allegedly admitted to the US in 2002 that it had a secret, enriched uranium programme.
The proposed power lines would provide the North with 2m kilowatts of electricity a year from the South's own power grid, and would be ready by 2008.
The power being offered is equivalent to the output of two large power stations and would help towards redressing North Korea's serious energy shortage.
But Mr Chung appealed for co-operation from other parties. He said the North also needed security guarantees if it was to sign up to any deal on giving up its nuclear programme.
The US gave vague assurances of security and economic aid at the last round of negotiations last year, but it was not enough to win over North Korea.
The BBC's Charles Scanlon in Seoul says the South Korean government has since seized the initiative, fearing that the confrontation between Pyongyang and Washington could escalate.
Seoul is worried that if the North were to collapse, it could be flooded with millions of hungry North Korean refugees.
Diplomatic efforts are gathering pace ahead of the next round of North Korean nuclear talks.
China's top envoy, Tang Jiaxuan, was expected in North Korea on Tuesday, and US Secretary of State Condoleezza Rice has arrived in Seoul.
Speaking in Tokyo, earlier on Tuesday, she called on the North to make a "strategic decision" to give up its nuclear weapons.
South Korea has also agreed to ship half a million tons of badly needed food aid to its northern neighbour.
The UN's World Food Programme raised the alarm about food shortages in the North earlier this year, saying there was a cereals gap up to October 2005 of 900,000 tons.
South Korea is one of the largest single donors of aid to the secretive communist state. It is the South's biggest donation to the North since 2000.
However, South Korea has repeatedly stated that full-scale aid as well as commercial exchanges are impossible as long as the nuclear issue is not resolved.
The UN World Food Programme is currently feeding some 6.5m North Koreans - nearly a third of the population.