North Korea's surprise pledge to probe Cold War kidnappings of Japanese nationals is an attempt to divide its foes that could benefit its nuclear and missile programmes if Tokyo eases sanctions in return, analysts say.

Thursday's announcement, which came after three days of talks in Stockholm, marked sudden progress on an issue that has obstructed ties between the two countries for years.

In exchange for re-opening its investigation into the whereabouts of people snatched off Japan's beaches in the 1970s and 1980s, Pyongyang has been promised a slackening of Tokyo's strictures.

Among the most significant is the possible easing of a ban on cash remittances from the thousands of ethnic Koreans living in Japan, who are loyal to the regime.

That could provide the North with much-needed hard currency for its weapons programmes, and could undermine international efforts to bring the regime to heel, said academic and activist Lee Young Hwa, a professor at Kansai University.

"Kim Jong-Un's regime has won a major compromise," he told AFP. "It has secured a way for money to flow to North Korea.

"Kim has issued an order to Chongryong (its defacto embassy in Japan) to press Korean business people to invest, which will mean cash flowing to North Korea.

"They badly want this money to maintain the regime and to fund the nuclear programme."

- Emotive issue -

Pyongyang has been under increasingly onerous international sanctions after carrying out nuclear and missile tests, with intelligence suggesting it is readying for a fourth atomic blast.

Any sanctions Japan eases will be unilateral ones imposed in addition to international ones.

Six-party talks aimed at getting the regime to abandon its programmes, involving both Koreas, Japan, the US, China and Russia, have stalled, with Washington and Seoul both declaring that Pyongyang had to show willing before they would sit down again.

North Korea's erratic behaviour has also irked Beijing -- its patron and long-time protector -- say commentators, leaving Pyongyang looking ever more isolated.

"Washington has put (North Korea) on the sidelines, so this is a gambit to try to shake up a stagnant situation that might open further opportunities," said Jeff Kingston of Temple University in Tokyo.

North Korea outraged Japan when it admitted more than a decade ago that it had kidnapped 13 of its nationals to tutor spies in Japanese language and customs.

Five abductees were allowed to return to Japan but Pyongyang insisted, without producing solid evidence, that the eight others had died.

The subject is highly charged in Japan, where there are suspicions that dozens or perhaps even hundreds of others were taken.

Emotive stories about the kidnapped individuals -- many of whom are now household names -- are never far from the pages of newspapers.

- 'Risky gamble' -

For Abe, who has declared the abduction issue "a top priority", getting the North Koreans to come clean would mark a significant victory that could buoy his store of political capital.

However, warned Toshio Miyatsuka, an expert on North Korea at Yamanashi Gakuin University, it is a risky gamble.

"The abduction issue is a hard one to resolve in a way that everyone will find satisfactory, and North Korea is an unpredictable partner," he told AFP.

"Accords are different from results. They are just standing on the starting line. A rough road lies ahead."

Aside from potential difficulties in holding Pyongyang to its promises for a "comprehensive and thorough" investigation, the end result may not be as rewarding as hoped, says Robert Dujarric at Temple University in Tokyo.

"If (Abe) gets something it will be good. But what can he get? At most a few abductees, but many are probably dead," Dujarric said.

Domestic blowback notwithstanding, engaging with North Korea at a time when the rest of the international community is looking to deepen its isolation risks irking Seoul and Washington.

While both will almost certainly cut Abe some slack, aware of how significant the issue is in Japan, they will be irritated nonetheless, said Kansai University's Lee.

"The Obama administration and South Korea will play it calm on the surface and say they understand Japan," he said, "But with the nuclear issue and missile problem, there is no way they can understand Japan's move."

However, said Dujarric, it is far from a disaster. "In the end these Japan-DPRK talks are unlikely to lead to much, so in the longer term it won't have much of an impact."

burs-hg/jom