South Korea's attempts to make its immigration rules more restrictive to reduce the number of unregistered immigrants here could easily backfire, a veteran diplomat said, adding that the current popularity of the Korean Wave is far from everlasting.

Kim Jae-shin, secretary-general of the ASEAN-Korea Center, noted much interest among people in Southeast Asia in learning about South Korea and its culture. However, he cautioned that making immigration procedures for citizens of the 10 countries of the Association of Southeast Asian Nations more difficult and harsh could potentially foster negative perceptions toward South Korea.

"We might be able to go all out to crack down on those who are living and working here illegally, but in exchange, that might trigger sweeping anti-Korea sentiment," said Kim, 67, who formerly served as ambassador to the Philippines and Germany.

Nearly 27 percent of Korea's 2.1 million foreign residents hail from the 10 ASEAN member countries, according to the latest data from the Justice Ministry. Data also shows that the number of people from Southeast Asian countries living in Korea with long-term visas jumped 47.5 percent from 2019 to August this year.

On the other side of what appears to be an outcome of ASEAN's Hallyu boom, crackdowns on foreign national residents here have become rampant and immigration rules more difficult and restrictive for potential travelers.

In the first half of this year, immigration authorities arrested nearly 24,000 people through crackdowns on unregistered foreign nationals here, including those from Southeast Asia. In the meantime, the number of unregistered foreign residents here fell about 4 percent to 414,000 over eight months to June.

In a recent high-profile case, South Korea forcibly deported two Filipina caregivers who had been participating in Seoul's foreign caregiver pilot project, after they had gone missing from their accommodations in Gangnam-gu, Seoul. They were later found working other jobs in Busan, citing excessive work and surveillance in the program.

Against this backdrop, Kim said South Korean authorities should not treat unregistered immigrants as massive criminals, given that such harsh treatment can easily influence the way people in other countries view South Korea.

"It is important to prevent illegal immigration. But there is a saying in Korea, 'Do not kill the entire cow just to fix its horns,'" Kim said, referring to an ancient proverb that warns not to go overboard and end up creating major problems out of the desire to fix a minor blemish.

"We have to deal with the problem of unregistered immigrants together. We have to live with it. It is one of the inevitable parts of our society that we need to embrace."

Meanwhile, the hashtag, #BanTravelToKorea, emerged on social media platform X last year, under which Thai tourists have been sharing their experiences of unfair treatment, discrimination and deportation by South Korean immigration officials.

The introduction of the K-ETA, or Korea Electronic Travel Authorization, has been one of the points of contention. Nearly 10,000 Thai travelers had to cancel group trips to South Korea in 2023 because some members of their groups were unable to gain K-ETA approval, according to data from the Korea Tourism Organization compiled by Rep. Kang Yu-jung of the Democratic Party of Korea.

Anti-Korea sentiment in the Southeast Asia could take a major toll on South Korea's export-driven economy, which is already going through a demographic crisis with its work-age population forecast to shrink by 10 million in 20 years, according to the Korean Peninsula Population Institute for Future in May.

"We often ignore that we cannot survive without exports," Kim cautioned.

South Korea's signing of a Comprehensive Strategic Partnership with the ASEAN bloc -- the highest type of partnership in ASEAN's diplomatic hierarchy -- provides the impetus for burgeoning people-to-people exchange, trade and investments. The number of young Southeast Asians studying in South Korea rose 55 percent from 2019 to 2023.

But these gains could be short-lived without the sustainability of mutual respect and amicable relations between South Korea and the 10 member countries of ASEAN via immigration policies. Kim recalled a Japanese restaurant he used to frequent in Seoul that eventually had to shut down when the relationship between South Korea and Japan hit a low point due to historical disputes.

The same can happen in the relations between South Korea and Southeast Asia, he said.

"The mantras of 'K-pop' and 'K-food' do not last forever," Kim said. "They exist (only) when we are have good relations (with our partner countries). Once their people start to hate us, there's no looking back."

Kim said the ASEAN-Korea Centre is working to create a positive atmosphere in which people from different cultural backgrounds can come together.

The eighth segment of Jeju Island's Olle trail -- spanning nearly 20 kilometers of the trekking path on the perimeter of the island -- is to be renamed "Jeju Olle 8th Trail: ASEAN-Korea Olle," on Nov. 8 to commemorate this friendship.

Programs for Southeast Asian and Korean students studying here will also be hosted. For example, the ASEAN-Korea Youth Summit will take place in Seoul in November. In a similar vein, the ASEAN-Korea Youth Network Workshop was held this summer in Seoul and Vientiane, Laos.

"In order to continue cooperation between ASEAN and Korea, and further expand people-to-people exchanges, winning the hearts and minds of ASEAN countries' people is crucial," Kim said. "We must strive to make ASEAN feel that Korea is a genuinely close friend and mutually helpful partner."

This article is part of a series examining the evolving relationship between the ASEAN member countries and South Korea, in celebration of the 35th anniversary of ASEAN-Korea Dialogue Relations, commemorated this October. -- Ed.