TOKYO - Japan said on Sunday it would extend economic sanctions against North Korea for another six months given the reclusive communist state's failure to reveal the fate of Japanese nationals it abducted decades ago.

"There is basically no progress in the abduction issue," the government's top spokesman, Chief Cabinet Secretary Nobutaka Machimura, told reporters.

"We are not in a situation in which we can stop or ease the sanctions," Kyodo news agency quoted Machimura as saying.

Japan is currently taking part in protracted six-country talks in Beijing aimed at coaxing North Korea to abandon its nuclear weapons ambitions.

At the same time, Tokyo is determined not to relax its own pressure on the impoverished Stalinist regime until Pyongyang comes clean on the fate of a number of Japanese citizens abducted by its agents decades ago.

Back in April, the government extended its sanctions until mid-October.

Tokyo initially imposed the measures, which ban North Korean imports and bar all North Korean ships from Japanese ports, after Pyongyang conducted its first nuclear test last October.

Japan's total trade with North Korea amounted to about $180 million in 2005, about half the figure in 2002, and trade dwindled further in 2006.

The abductees' fate is a highly emotive issue in Japan.

Pyongyang admitted in 2002 that its agents had kidnapped 13 Japanese in the 1970s and 1980s, five of whom have since been repatriated.

North Korea says the other eight are dead, but Tokyo wants better information about their fate, as well as information on another four people it says were also kidnapped.