The US is considering resuming food aid to the country it regards as a rogue state amid fears that many North Koreans face starvation after a harsh winter.
Special envoy Stephen Bosworth told the Senate Committee on Foreign Relations the Obama administration was assessing North Korea's need for assistance after the reclusive Asian nation requested it.
The US government suspended food handouts to the impoverished North in 2009 after monitors were expelled, and a resumption would be politically sensitive because of concerns it could be seen as a reward for bad behaviour.
In the past eight months Pyongyang has been accused of launching two unprovoked military attacks on rival South Korea and has revealed a uranium enrichment programme that could provide it a new means of generating material for nuclear weapons.
The top US diplomat for East Asia, Kurt Campbell, told politicians any decision would be taken in close co-ordination with South Korea.
Asked whether food aid could ultimately ease economic pressure on the North, which would effectively allow it to put more resources into its nuclear programmes, Mr Campbell said North Korea had shown historically that it was willing to allow "enormous suffering" among its people. Many starved during the 1990s, he said.
"The choice here is whether these people are allowed to starve. It's a humanitarian issue, not a political one," he added.
Five non-government US-based aid groups who visited North Korea last month reported children suffering from acute malnutrition and people foraging for wild grasses and herbs.
Summer floods and the bitterest winter in decades had cut principal crop harvests by more than half, and North Korean authorities estimated that food stocks would be exhausted by mid-June, the groups said.
The United Nations, which has a continuing, but underfunded food distribution programme in North Korea, is also conducting a food needs assessment there.