Japan wants more details about abductees such as Megumi Yokota
Japanese and North Korean envoys have begun talks in the Mongolian capital, Ulan Bator, to resolve long-standing disputes between the two sides.
The talks will focus on a row over Japanese nationals abducted decades ago to train North Korean spies.
Tokyo wants the issue resolved before diplomatic ties with Pyongyang can be normalised.
The two countries last held bilateral talks in Hanoi, Vietnam, in March, but no progress was made.
The meeting is one of several working-level discussions being held as part of a multilateral deal aimed at ending North Korea's nuclear programme.
Japanese negotiator Yoshiki Mine said that a number of topics would be discussed.
Snatched in the '70s and '80s
Used as cultural trainers for N Korean spies
Five allowed home in 2002
Five children now freed from N Korea
Eight said to be dead, others missing
"Our goal is to normalise relations after solving outstanding problems including the abduction, nuclear and missile issues and settling issues from an unfortunate past," he said.
"All of them are difficult problems, and I wish to hold talks in a sincere manner."
The abduction issue has long been an obstacle to dialogue between the two sides.
North Korea admitted in 2002 that it had abducted 13 Japanese nationals in the late 1970s and early 1980s.
It has returned five of them and says the remaining eight are dead. It says the issue has now been resolved.
But Japan wants concrete proof of the deaths and believes that several more of its citizens were taken.
North Korea, meanwhile, is seeking reparations for Japan's 35-year colonisation of the Korean peninsula.
The talks are due to last for two days.