Japan has taken its campaign to rewrite its wartime history into the classroom with demands that a US publisher remove “inaccurate” descriptions of tens of thousands of women who were forced to work as sex slaves before and during the war.

The move by the country’s foreign ministry comes after a Japanese publisher said it would delete text and depictions of the women, most of whom were from the Korean peninsula, from textbooks used in high schools.

Suken Shuppan, a Tokyo-based publisher said it had successfully applied to the education ministry to remove references to “comfort women” – a euphemism for sex slaves commonly used in Japan – from three social studies and politics textbooks.

The publisher has refused to explain why it had sought for permission for the change.

The education ministry approved the revision, which applies to texts that will be used at the start of the new academic year next spring.

In 2014 Japan’s conservative administration, led by Shinzo Abe, tightened curriculum guidelines that require publishers to state the government’s official view on contentious issues.

“The idea is to strengthen state control over textbooks,” said Mina Watanabe, at the Women’s Active Museum on War and Peace in Tokyo. “What Suken Shuppan did was an over-reaction. It should explain why it erased the terms and the government should explain why it accepted the change.”

Under Abe, a nationalist, Japan has attempted to play down controversial episodes in its modern history, including the Rape of Nanking, the treatment of Allied prisoners of war, and the coercion of as many as 20,000 women, most of whom were from the Korean peninsula, to work at military brothels.

While Abe has stopped short of reversing an official apology to the women issued in 1993 by the then chief cabinet secretary, Yohei Kono, he supports the revisionist view that the women were not coerced, sparking anger in South Korea.

The Kono statement acknowledges that many comfort women were recruited against their will, and that the military was often involved, either indirectly or directly, in the setting up of “comfort stations”.

Experts who helped write a 2007 US House of Representatives resolution calling on Japan to acknowledge and apologise for the role imperial forces played in coercing the women say Abe is quietly undermining the official apology as Japan prepares to mark the 70th anniversary of the end of the Pacific war with a new “forward-looking” statement from Abe.

“[He] is trying to have it both ways,” said Larry Niksch, at the Center for Strategic and International Studies in Washington. “He says things that encourage the history revisionists, but he also makes statements that put some distance between himself and the revisionists.

“My sense is that he will not change the Kono statement this year. He has said too many times that he won’t change it. However, he might not oppose a move in the Japanese diet to pass a resolution refuting the Kono statement.”

Disagreement between Tokyo and Seoul over the comfort women issue has prevented Abe from holding a summit with his South Korean counterpart, Park Geun-hye, even though both leaders have been in power for two years.

The South Korean foreign ministry said Suken Shuppan’s move risked further damaging ties. “Historical facts cannot be modified or deleted,” a ministry official was quoted by the Asahi Shimbun as saying. “If the Japanese government repeats such nonsense, it will become a serious obstacle to the improvement of ties between South Korea and Japan.”

The authors of the Japanese textbooks will tweak passages to render them more ambiguous. The new material will mention that South Koreans are seeking compensation through the Japanese courts, but won’t explain why, Kyodo News said.

This is the first time that pressure has been applied to publishers in the US, where some Korean-American communities have erected memorials to the comfort women, sparking protests from Tokyo.

Japan’s foreign ministry requested that McGraw-Hill delete a passage containing a reference to comfort women from a text on world history used by high schools in California. The passage says that Japan’s imperial army “forcibly recruited, conscripted and dragooned as many as 200,000 women aged 14 to 20” to serve in military brothels.

But at a meeting with officials from the Japanese consulate in New York, McGraw-Hill refused to change the passage, saying it was “based on historical facts,” according to the Sankei Shimbun.

Watanabe welcomed McGraw-Hill’s refusal to bow to pressure, but said Japanese children risked growing up ignorant of their country’s past.

Censoring textbooks would be devastating for pupils, she said. “Children in neighbouring countries know the truth about the Japanese military’s conduct in Asia … only Japanese children would be kept in the dark, but they have the right to learn the facts of history.”

The revisionists received a boost last summer when the Asahi Shimbun, Japan’s only liberal broadsheet, admitted it had run a series of erroneous articles in the 1980s and 90s about comfort women.

The articles repeated claims by Seiji Yoshida, a former Japanese soldier who said he had helped round up women on the South Korean island of Jeju during the war. Yoshida’s testimony has since been discredited.

Abe and his supporters have since claimed that the Asahi articles were reflected in global media coverage of the comfort women issue and had damaged Japan’s image overseas. An independent investigation, however, found there was “no clear evidence” to support Abe’s claim.