South Korea on Monday shelved a proposed trip by Foreign Minister Yun Byung-Se to Tokyo in protest at visits by Japanese cabinet ministers to a controversial war shrine.
"We express deep concern and regret over the visits... to the shrine that glorifies an invasion that inflicted great loss and suffering on Japan's neighbours," the foreign ministry said in a statement.
Japan's Deputy Prime Minister Taro Aso and Keiji Furuya, the chief of the National Public Safety Commission, separately visited the Yasukuni shrine on Sunday.
Internal Affairs Minister Yoshitaka Shindo also visited the shrine at the weekend, his office told AFP on Monday.
The memorial, which honours around 2.5 million war dead -- including 14 leading war criminals -- is seen by Japan's Asian neighbours including China and South Korea as a symbol of Tokyo's imperialist past.
Seoul's foreign ministry called the latest visits to the shrine "anachronistic" and strongly urged Tokyo to "take responsible action" to win back the trust of its neighbours.
Discussions on a visit to Japan later this week by Foreign Minister Yun -- his first since taking office in March -- were called off in protest, a ministry spokeswoman said.
Yun had been planning to meet his Japanese counterpart Fumio Kishida to discuss ties, with both countries under new leadership.
"But the plan has been cancelled after the Japanese officials' visit," the spokeswoman told AFP without elaborating.
Tokyo responded robustly, saying the visits were made in the ministers' personal capacity and that the government had no official involvement.
"Each country has its own position, and that kind of thing should not affect diplomacy," Japan's top government spokesman Yoshihide Suga told reporters in Tokyo.
"Ministers visiting the shrine as private citizens is their own personal affair and the government won't comment on such decisions."
Visits to the shrine by government ministers and high-profile figures spark outrage in China and on the Korean peninsula, where many feel Japan has failed to atone for its brutal aggression in the first half of the 20th century.
Prime Minister Shinzo Abe did not make a pilgrimage but paid for equipment made of wood and fabric -- which bears his name and title -- which is used to decorate an altar.
Relations between Tokyo and Seoul are already strained by a territorial row over a Seoul-controlled chain of islets in the Sea of Japan (East Sea).