The talks scheduled for scheduled for October 2-4 will be only the second ever summit between the leaders of North and South Korea.
 
Both countries have remained officially at war since the 1950-53 conflict.
 
The US team of nuclear experts touring North Korea is led by Sung Kim, the US state department director for Korean affairs and a deputy negotiator in the disarmament process.
 
Hopeful sign
 
North and South Korea have never signed a
peace treaty and remain technically at war [AP]
Officials say the visit is seen as a hopeful sign that, almost a year after North Korean first tested a nuclear weapon, it is serious about permanently shutting down its nuclear plants.
 
The experts will report back to the next session of six-party talks, expected later this month.
 
The talks bring together envoys from North and South Korea, Russia, China, Japan and the US.
 
In a landmark deal agreed in Beijing in February, North Korea agreed to declare and disable all its nuclear programmes in return for aid, security guarantees and major diplomatic benefits.
 
In July it shut down its only operating reactor at the Yongbyon complex in return for 50,000 tonnes of fuel oil.
 
The next step is to permanently disable all it nuclear facilities by encasing them in concrete or some other method which the experts will advise on.
 
If the North declares and disables all its plants it will receive another 950,000 tonnes of fuel oil or equivalent energy aid.