The Osaka Municipal Government will ask San Francisco’s city council to carefully examine a resolution that supports establishment of a statue honoring the “comfort women” who worked at wartime Japanese military brothels, officials said.

Osaka City Hall will send a letter to the assembly of its U.S. sister city expressing concerns that erecting such a statue could negatively affect the city-to-city relationship as well as diplomatic ties between Japan and the United States.

The letter will be sent by Sept. 8, when the San Francisco council, known as the board of supervisors, is scheduled to start debate on the resolution, Osaka officials said Tuesday.

“It’s true that women’s human rights were abused during World War II, but it’s not fair to say only Japan did something special,” Osaka Mayor Toru Hashimoto said at a news conference in July, when he indicated his plan to send such a letter to San Francisco.

The comfort women were mainly Asian women forced into brothels for the Japanese military before and during World War II.

According to the Osaka Municipal Government, the San Francisco city council will discuss a resolution that states an estimated 200,000 Asian and other women were forced to serve as sex slaves for the Japanese military during the war.

In 2013, the outspoken Hashimoto said Japan’s wartime system of sexual servitude was “necessary to maintain discipline” in the Japanese military before and during World War II, sparking criticism at home and abroad. He later said he did not personally hold the view that those women were necessary but was only describing the situation during wartime.

The San Francisco council subsequently adopted a resolution condemning Hashimoto’s remarks. Hashimoto also canceled a planned visit to San Francisco after he received a letter from a senior San Francisco official that urged him to do so due to the furor caused by his comments.