Tokyo issued a travel advisory to Japanese citizens visiting South Korea ahead of crucial anniversaries this week, urging them to be cautious about safety as ties between the neighbors worsen over trade and historical issues.

On Wednesday, South Korea commemorates the so-called comfort women — a euphemism used in Japan to refer to women who provided sex, including those who did so against their will, for Japanese troops before and during World War II. On Thursday South Korea marks a national day of liberation from Japanese rule, which ran from 1910 to 1945.

Japan's Foreign Ministry on Tuesday advised Japanese residents in South Korea and visitors to be careful and avoid areas in which Japan-related protests and gatherings are expected to be held on Wednesday and Thursday.

The ministry issued similar travel advisories earlier this month ahead of protests expected near the Japanese Embassy or consulates.

Relations between the two countries have deteriorated since rulings by South Korea's Supreme Court last year ordering Japanese companies to compensate South Koreans who were conscripted as forced laborers during World War II.

Japan hit back at South Korea on Tuesday for removing Tokyo's fast-track trade status, with industry minister Hiroshige Seko saying Seoul had failed to explain its reason for the latest move in an escalating trade row.

Seoul's action was a response to Japan's announcement this month that it was dropping South Korea from its own "white list" of countries that have enjoyed minimum trade restrictions, citing an erosion of trust.