South Korea offered aid worth 5 billion won ($4.7 million) to flood-hit North Korea on Wednesday, its first such proposal since Pyongyang's deadly island attack last November sent relations into deep freeze.

The North, which even in normal times struggles to feed its people, has reported dozens of casualties, thousands homeless and large areas of farmland flooded following a storm and torrential rain this summer.

The South's offer came amid signs of an easing of high cross-border tensions. Nuclear negotiators from the two sides held rare talks last month on the sidelines of a regional security meeting in Bali.

Seoul's unification ministry said the offer of medicine and daily necessities was made through the South's Red Cross. If the North accepted it, talks would be held on shipping arrangements across the tense border.

Ministry officials said the new aid package would not include rice and cement.

Official media in the communist state has said a tropical storm and heavy rain in June and July left dozens either dead, injured or missing, destroyed 2,900 homes and flooded more than 60,000 hectares (148,200 acres) of farmland.

Floods are common in North Korea, mainly because of its lack of disaster-control infrastructure and severe deforestation of hillsides.

Ties have been icy since the South accused its neighbour of sinking a warship in March 2010 with the loss of 46 lives.

Despite that incident, for which the North denied responsibility, the South in September 2010 promised a 10 billion won flood aid package.

But it suspended shipments after the North killed four South Koreans in a bombardment of a border island last November.

A global relief agency said separately it has allocated more than $590,000 to help the flood victims.

The International Federation of Red Cross and Red Crescent Societies said on its website it has released more than 450,000 Swiss Francs to help over 15,000 people through the North's Red Cross.

The unification ministry, which must by law authorise all contacts with the North, has also given the go-ahead for a private group to deliver flour aid.

The Korean Council for Reconciliation and Cooperation has sent six members across the border to check that shipments are being delivered to needy children and not diverted to the military.

The council so far has delivered 600 tonnes of flour and plans to send a total 2,500 tonnes of flour by the end of August.

The South in 2008 stopped an annual government shipment of 400,000 tonnes of rice to its impoverished neighbour as relations began to sour.

Authorities allowed some civilian groups to keep sending aid, but suspended approval of flour shipments after the island attack.

The reconciliation council's initial shipment on July 26 was the first flour aid since the suspension.

Seoul officials believe flour can easily be diverted to the North's powerful military unless deliveries are monitored.

The North has relied on international aid to help feed its people since a famine in the 1990s killed hundreds of thousands. This year it asked the United States and other nations for food assistance.

United Nations agencies estimate that six million people there are in urgent need of food.

UN secretary-general Ban Ki-moon, quoted by Yonhap news agency from New York, appealed Tuesday for more food help.

"The UN views North Korea's food conditions as being at a serious level and hopes for the international community's active contributions," he said.

Ban also, however, said that the United States and North Korea remain far apart after exploratory talks on Pyongyang's nuclear disarmament, but conceded that both sides are trying to narrow the gap.

North Korea's first vice foreign minister Kim Kye-Gwan held talks in New York with US officials last Thursday and Friday as part of diplomatic efforts to restart long-stalled six-nation nuclear negotiations.