For Japan and South Korea, the resumption of top-level dialogue in and of itself is a major step forward.

Meeting for their first official talks in about 15 months, Japanese Prime Minister Shinzo Abe and South Korean President Moon Jae In sent one main message: They will prevent bilateral ties from spiraling out of control.

That is a relief to diplomats who had until recently expected that the worst may be yet to come for the Asian neighbors due to disagreements over compensation for wartime labor and Japan's tightening of export controls.

But Japan and South Korea are still in a state of "mutual distrust" and a return to what Abe has described as a "healthy relationship" won't be easy, experts say. Continued dialogue can only boost their chances of mending fences.

"What we've seen over the past year are Tokyo and Seoul making their own cases heard and hoping that the other side would acquiesce. If they stick to an 'all or nothing' mentality, they will never meet halfway," said Hideki Okuzono, an associate professor of South Korean politics and diplomacy at the University of Shizuoka.

"The summit was important in that it signaled some improvement in ties between the leaders who had harbored mistrust," Okuzono said.

In an atmosphere that was "tense at times but not hostile," about a third of the 45-minute meeting Tuesday in Chengdu, southwestern China, was spent on the contentious issue of compensation for wartime labor, according to a senior Japanese government official. The spat had sent bilateral ties to their lowest point in years.

But Abe and Moon failed to bridge differences in their basic position and no new proposals were made for resolving the dispute, sparked by South Korean court rulings a year ago that ordered Japanese firms to compensate for wartime labor during the 1910-1945 colonization of the Korean Peninsula.

Japan has consistently argued that the ball is in South Korea's court and that Seoul has to come up with steps to turn the situation around. This is based on the view that the compensation issue was settled under a 1965 bilateral accord, which Tokyo sees the court orders as having breached.

A turning point came when South Korea decided not to terminate a military intelligence sharing pact in late November, leading to some softening in Japan's stance. It was Abe himself who announced arrangements were being made for his meeting with Moon.

That was followed by the submission of a bill in the South Korean parliament as the dispute over wartime labor has dragged on to seek "voluntary" donations from citizens and businesses from the two countries to be used as compensation.

Since details of the plan emerged, Japanese government officials have refrained from comment and instead largely taken a wait-and-see stance, a change from June when Tokyo rejected outright Seoul's proposal to create a fund with an eye to Japanese firms named in the lawsuits participating.

Tuesday's meeting was an opportunity for Abe and Moon to clear up uncertainty or doubts over how they can find a solution to the wartime labor issue, though neither side broached the topic of the South Korean bill, according to a Japanese government source.

Japan is apparently concerned about whether the bill will be compatible with the 1965 agreement regarding the right to seek compensation and how much Moon and his government will be committed to the initiative.

The envisaged plan is seen as the most viable so far but its feasibility is still in doubt due to domestic opposition in South Korea.

Okuzono said there is no "panacea" for repairing ties. South Korea's donation plan may not be perfect but appears to have been carefully thought out so as not to cross Japan's "red line," he said.

However, suspicion runs deep in Japan after seeing the Moon administration's disbandment earlier this year of a Japan-funded foundation set up under a 2015 bilateral accord to support former comfort women.

"It is a proposal by a South Korea that unilaterally disbanded the foundation. I wonder how convincing it can be," said Fumio Kishida, policy chief of the ruling Liberal Democratic Party who was foreign minister at the time of the agreement.

In a whirlwind month, the General Security of Military Information Agreement between Japan and South Korea was saved amid U.S. pressure, while tensions somewhat eased over trade.

Those issues should not have been linked to the dispute over compensation for wartime labor, said Yasuyo Sakata, a professor of East Asian security at Kanda University of International Studies.

The first priority is to "untie each knot," Sakata said.

"Wartime labor is a deep-rooted issue that cannot be solved so easily," she said. "What needs to be done at the least is to prevent it from getting worse and worse, and control damage."

As the summit kicked off, Abe and Moon touched on the importance of bilateral ties. Moon, whose administration has maintained that the judicial decisions should be respected, said the nations are inseparable despite the difficulty they are now experiencing.

"Japan and South Korea will need to get over it," Okuzono said. Referring to the South Korean bill to resolve the wartime labor issue, he said, "The plan can serve as a starting point for discussion."

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