N Korea winding down its nuclear power plant
The team will work on disabling the reactor in Yongbyon which produces weapons-grade plutonium, as well as other facilities.
Under a February agreement, North Korea promised to abandon its nuclear ambitions in return for 1 million tonnes of oil as well as political concessions.
Six-nation negotiations also involved China, South Korea, Japan and Russia.
The U.S. delegation visiting North Korea will begin dismantling the reactor within the next few days.