In a sign of the deep-seated rancor between Seoul and Tokyo, more South Koreans would back their neighbor to the north if it went to war with Japan, according to a new survey by a state-sponsored think tank in Seoul.

The survey, conducted by research fellow Lee Sang Sin, was presented Wednesday as part of the Korea Institute for National Unification’s 11th annual Peace Forum, and comes amid increasingly fraught ties strained by rows over trade and history.

“Under a rather extreme hypothetical situation in which war may break out between North Korea and Japan, 45.5 percent would choose to help North Korea, and 15.1 percent Japan,” the survey showed. About 39.4 percent responded that they “have no idea.”

The research found that responses from across the political spectrum backed the idea of supporting the North in the event it went to war with Japan. Nearly 53 percent of those who identify with President Moon Jae-in’s Democratic Party and 43 percent of those who back the conservative opposition Liberty Korea Party, as well as 41 percent of those with no party affiliation, supported such a move.

The survey also found that more than a third viewed Japan as a future military threat to South Korea, while 61 percent viewed it as a threat currently.

Lee said the results were not surprising, noting a similar poll that has been carried out since 2007 found that more South Koreans support the North Korean national soccer team over that of the U.S.

“For South Koreans, North Korea is like a troublemaker in the family, a black sheep,” Lee told The Japan Times. “We hate and despise North Korea, but at the same time, we don’t want to see North Korea beaten down by other countries.”

And while the two Koreas are divided by “ideology and other conflicts in Korean society, the attitude toward Japan strengthens the homogeneity of South Korean society,” Lee said.

“Similarly, whenever South Korea has a territorial dispute about Dokdo with Japan, North Korea has sided with South Korea,” he said of the South Korean-controlled islets in the Sea of Japan that are also claimed by Tokyo, which calls them Takeshima.

Relations between the two Asian neighbors have plummeted to their lowest point in years after South Korean Supreme Court rulings last year ordered Japanese companies to compensate wartime forced laborers during Japan’s 1910-1945 colonial rule of the peninsula. Japan says that such claims were settled under a 1965 treaty.

Bilateral tensions escalated when Japan imposed stricter export controls on some key materials needed by South Korea’s tech industry in July and dropped the country from a list of trusted trade partners the following month. South Korea retaliated by removing Japan from its own whitelist of trade partners.

The trade spat has since spilled over onto the security front, worrying the two countries’ top ally, the United States.

Seoul is planning to end a military intelligence-sharing pact with Tokyo, a move that would affect trilateral security cooperation with Washington as North Korea continues to build up its nuclear and missile programs and as Chinese military power grows.

Asked if they support or oppose the South Korean government’s decision to terminate the General Security of Military Information Agreement (GSOMIA), which is set to formally expire Nov. 23, 72 percent backed the decision, including 88 percent from those who identify with the Democratic Party, 63 percent of those who back the Liberty Korea Party and 67 percent of those who listed no party.

But despite the large majority who support scrapping the deal, the survey noted that the majority of South Koreans do not want relations with Japan to be completely broken off.

“The Korean public supports the termination of GSOMIA with an overwhelming margin,” Lee said. “But if some conditions are met — Japan’s trade ban reversal, and maybe an apology — then I believe South Koreans are willing to reinstate GSOMIA.”

Still, this animosity aside, in one sign of the importance South Koreans appear to place on improving soured ties with their neighbors, a whopping 83.4 percent said a summit between Moon and Prime Minister Shinzo Abe is necessary.

The survey, entitled “The Situation in Northeast Asia and South Koreans’ Perception,” saw Lee interview 1,000 participants in person in three phases — from April 5 to 25 last year; from April 5 to 25 this year; and from Sept. 17 to Oct. 8 this year.