Talks between Tokyo and Pyongyang on Japanese citizens abducted during the Cold War opened Tuesday in Beijing with Tokyo's envoys giving their North Korean hosts a diplomatic rebuke over missile launches.
Sunday's test launch of two short-range Scud missiles was "extremely regrettable", foreign ministry official Junichi Ihara, the head of Japan's delegation, told his North Korean counterpart Song Il-Ho.
At the start of talks at North Korea's embassy in the Chinese capital, Ihara stressed the missile launch was "incompatible" with the substance of previous North Korean commitments made to Japan and to agreements at Six-Party nuclear talks.
Ihara called on the nuclear-armed North not to repeat the launches, and to respond to the demands of the international community, but Song defended Pyongyang's actions.
"The rocket launch... was carried out smoothly without having the slightest impact, not only on regional peace and security but on international navigation order and ecological environment," he said.
The talks were held in a huge meeting room under two giant, imposing pictures of North Korea's founder Kim Il-Sung and his son, Kim Jong-Il, who died in December 2011.
The younger man was in turn succeeded by his own son Kim Jong-Un, as the Kim dynasty maintained its hold on the secretive, isolated state.
It is unusual for foreign journalists to be allowed into the embassy.
The North has promised to use the Beijing meeting to "explain about the organisation, composition and persons in charge" of a committee it has set up to reinvestigate the abductions of Japanese in the 1970s and 1980s, Tokyo officials said previously.
North Korea admitted in 2002 that it had kidnapped 13 Japanese citizens to train its spies in Japanese language and customs. The subject is highly charged in Japan, where there are suspicions that dozens or perhaps even hundreds more were taken.
Ihara and Song were chief negotiators at talks between the two sides held in Sweden in May, which marked a major breakthrough in their very strained relationship and the most positive engagement between Pyongyang and the outside world in many months.
"What is truly important is what comes next," Ihara said Tuesday. "It's necessary to firmly and steadily implement this agreement and make it effective."
The North's missile launch came three days after Pyongyang fired what were believed to be three short-range missiles into the sea.
The show of force comes ahead of a state visit to Seoul by Chinese President Xi Jinping Thursday to discuss issues including the North's nuclear weapons programmes.