The relationship between South Korea and Japan has deteriorated to the point that their leaders may skip a bilateral meeting on the sidelines of the Group of 20 summit to be held in Osaka, Japan, on Friday and Saturday.

The drawn-out discord between the neighboring countries over their unfortunate shared history is now leading the two sides to antagonize each other in undiplomatic ways.

South Korea was ready to meet, but Japan did not seem to be in the same state of mind, a Cheong Wa Dae official said Tuesday, confirming that President Moon Jae-in would not meet bilaterally with Japanese Prime Minister Shinzo Abe at the G-20 summit.

The confirmation came after Abe ruled out the possibility of a one-on-one meeting with Moon, saying his schedule as chair of the multilateral forum had already been filled with bilateral talks with other leaders.

It is just beyond reason that the Japanese leader has no time to meet with Moon when he can find the time for 15 rounds of bilateral summits on the sidelines of the multilateral forum. It might have been less insulting if Abe had simply said he did not want to talk with the South Korean president.

The Cheong Wa Dae official countered Abe’s remarks by saying Moon’s schedule had also been filled. This reaction was just as emotional and undiplomatic.

The possibility of Moon-Abe talks being held was virtually eliminated last week, when Tokyo spurned a proposal from Seoul that companies from both countries create a joint fund to compensate victims of Japan’s wartime forced labor.

True, South Korea’s presidential office had initially dismissed the idea raised by some experts late last year as “senseless,” while Japan had expressed willingness to take it into consideration. Nevertheless, it was rude for the Japanese government to turn down a formal proposal from Seoul less than an hour after it had been announced.

In October, South Korea’s Supreme Court ordered Japanese firms to compensate Korean victims of forced labor. The top court recognized the victims’ rights to claim damages individually, dismissing Tokyo’s assertion that all reparation issues were settled under a 1965 accord that normalized ties between the two nations.

Later last year, the Moon administration virtually scrapped a 2015 accord his predecessor had concluded with Tokyo to resolve the issue of wartime sexual slavery, when it decided to dissolve a foundation set up with funding from the Japanese government to support victims.

The rekindled disputes over issues stemming from Japan’s 1910-45 colonial rule of the Korean Peninsula were complicated by Tokyo’s allegation in December that a South Korean destroyer had locked its targeting radar on a Japanese surveillance plane.

The aborted meeting between Moon and Abe at the G-20 summit would further exacerbate the strained ties between their countries.

It is regrettable that political leaders on both sides seem to be using inflammatory historical issues to their domestic political advantage at the risk of harming the economic and national security interests of the two countries.

South Korea, in particular, cannot afford to let trade with and investment from Japan continue to decrease amid growing global economic uncertainties, including the escalating trade tensions between the US and China.

As a US official recently noted, the frayed relationship between Seoul and Tokyo would make it hard to ensure success in negotiations with North Korea on dismantling its nuclear arsenal.

It makes little sense that South Korea’s Foreign Ministry excluded cooperation with Japan, while emphasizing close communications with China and Russia, in its recent report to the parliament on ways to resolve the North Korean nuclear issue.

Seoul is expected to come under increased pressure from US President Donald Trump to improve ties with Tokyo during his two-day visit here following the G-20 summit.

South Korea and Japan should not let their relationship drift further by continuing to lay blame on each other.

Speculation has risen that a Moon-Abe summit will be set up after Japan’s Upper House election that is set for July 21, as Abe may feel less need to fan anti-South Korea sentiment among voters.

The two leaders should meet soon to work out any sort of improvement to the chilled relationship between their nations.

A recent survey of South Koreans and Japanese should serve to prod them to move in that direction.

About 83 percent of South Korean respondents and 44 percent of Japanese polled agreed it was necessary to strengthen economic cooperation, among other collaborations, while the negative response stood at only 8.9 percent and 11.5 percent, respectively.