TOKYO (Reuters) - Japan will likely extend its sanctions against North Korea because of Pyongyang's delay in reporting into its abductions of Japanese citizens decades ago, the Nikkei business daily reported on Saturday without citing sources.

The government is poised to decide next Tuesday on an extension to a trade embargo on North Korea, a ban on North Korea charter flights and a prohibition on North Korean ships entering Japanese ports, the Nikkei said.

Japanese government officials were unavailable for comment.

In 2002, North Korea admitted kidnapping 13 Japanese citizens in the 1970s and 1980s to help train spies. Five of those abductees and their families later returned to Japan.

North Korea said that the remaining eight were dead and that the issue was closed, but Japan has been pressing for more information.

Last July, Japan lifted some of sanctions against North Korea, such as easing travel curbs, in return for Pyongyang's reopening of an investigation into the abductees.

Tokyo will leave the partial easing of some sanctions unchanged but wants to keep pressure on Pyongyang for not disclosing facts about the kidnappings and the launch of missiles early this month, the Nikkei report said.

North Korea was supposed to issue an initial report on a probe into the kidnappings last September but postponed it saying the investigation was at an early stage.

There were informal talks among officials between the two sides this month and Japan's delegation threatened to impose tougher sanctions if the report on the abduction probe was delayed further, the Nikkei said.

(Reporting by Kaori Kaneko; Editing by Michael Perry)