A US aid shipment arrived Saturday in North Korea with around 90 tonnes of emergency supplies for the flood-hit nation, the organisation conducting the operation said.

"The plane has landed, and the relief supplies are in DPRK," Todd Shearer, a spokesman for US-based Christian relief group Samaritan's Purse, told AFP, using the country's official name.

Impoverished but nuclear-armed North Korea has seen international aid supplies reduce in recent years as tensions on the Korean peninsula have racked up.

The aid delivered Saturday is being funded by the US government and Washington had said it was to arrive at the weekend in Pyongyang.

State Department spokeswoman Victoria Nuland said Friday that the United States "remains deeply concerned about the well-being of the North Korean people, and this humanitarian assistance is not linked to any political or security issues".

Washington granted $900,000 in funding for the supplies, while Samaritan's Purse said it furnished $1.2 million for the airlift.

Samaritan's Purse says the aid includes blankets, plastic sheeting for shelters, hygiene kits, water filtration systems and medical supplies.

North Korean state media said August 5 that floods in the country triggered by torrential rain had killed 30 people and destroyed almost 7,000 houses.

More than 15,000 people were left homeless by the floods, which also inundated 48,000 hectares (120,000 acres) of farmland, "seriously affecting this year's grain output," the Korean Central News Agency said.

It added 350 factories and public buildings also collapsed.

Separately, North Korea has requested overseas food aid and in May invited a US envoy to assess its needs. Relief groups have said North Korea faces imminent shortages, although many US lawmakers have been sceptical.

Washington has for months been withholding a decision on sending food aid to the country until Pyongyang tackles US concerns over whether it will be distributed to the needy.

UN Secretary General Ban Ki-Moon has called on the world community to send aid to North Korea regardless of political considerations.