A pedestrian is reflected on a campaign poster on Japan's abduction issue, on a street in Tokyo July 3, 2014. Japan decided on Thursday to ease some sanctions on North Korea in return for its reopening of a probe into the fate of Japanese citizens abducted by the reclusive state decades ago, as a fresh report emerged that some of them were alive. The poster reads "we will get them back at any cost". (Yuya Shino/Reuters)

Japan decided Thursday to lift or ease several sanctions against North Korea, a bid to improve relations that comes as Pyongyang reinvestigates decades-old kidnappings of Japanese nationals.

The sanctions that Japan rolled back were unilateral, and Tokyo will continue to abide by resolutions imposed by the U.N. Security Council. Still, Japan’s move is delicate, coming at a time when the United States and its allies have tried to hold a firm line on North Korea, saying relations will improve only if the North curbs or dismantles its illicit nuclear weapons program.

Japan will lift certain travel bans and loosen its oversight of remittances. It will also allow port calls by North Korean ships for humanitarian purposes. The easing of the sanctions is largely symbolic, but some analysts say it could mark the beginning of a broader warming if North Korea returns abducted Japanese citizens.

Those abductions, which took place primarily in the 1970s and 1980s, have long been Japan’s top priority with the North. This week, Japanese and North Korean diplomats met in Beijing, and Tokyo came away with information about a new investigative committee formed by Pyongyang to look into the issue.

Japanese Prime Minister Shinzo Abe said Thursday that the North’s panel appeared to be credible and involved members of some of the authoritarian country’s most powerful organs.

“This is only a start,” Abe said. “We will do our utmost to resolve the issue.”

In a state-sponsored effort, the North abducted dozens and possibly hundreds of Japanese citizens, some of whom were used in espionage training programs. In 2002, in another flurry of diplomacy, the North admitted to kidnapping 13 citizens. The North said five were still alive, and they were returned to Japan. North Korea claimed the others were dead, but Japan says the explanations for these deaths are dubious. North Korea handed over the supposed remains of two victims, but DNA tests found no match.

Officially, Japan recognizes 17 kidnap victims. And the government says on a Web site devoted to them that “until this issue is resolved, there can be no normalization of relations with North Korea.”

But it was unclear whether the North’s reinvestigation would lead to any kind of breakthrough. A 2008 pledge by the North to reexamine the cases fell through.

Japanese Chief Cabinet Secretary Yoshihide Suga said Thursday that an initial report on the abduction issue could be received from North Korea by the end of the summer.

“After long years of waiting, North Korea has always shut its door,” Suga said. “But we’ve finally found a way to open their door.”

Some analysts say that North Korea could be newly motivated to deal with Japan as its ties with China show signs of strain. Chinese President Xi Jinping visited Seoul on Thursday, becoming the first Chinese leader to travel to South Korea ahead of the North.

But the North continues to take steps that leave Japan, as well as the United States, uneasy. In the past few days, Pyongyang has fired a series of short-range missiles. North Korea’s state-run media on Thursday quoted a spokesman for the Korean People’s Army as saying that the testing of “high-precision tactical guided missiles” would go on undeterred, “targeting the citadel of the gangsters.”