Facing an audience Monday at Harvard University in Boston, Prime Minister Shinzo Abe tried to dodge the politically explosive issue of wartime "comfort women" by reaffirming his earlier stance upholding a key 1993 government apology for their ordeal.

"Comfort women" is the euphemism Japan used to refer to females who were forced to work at Japanese wartime military brothels in the 1930s and 1940s.

During a question and answer session after Abe's speech on the Japanese economy, a Harvard sophomore asked him if he denies that the Japanese government and military were directly involved in forcing "hundreds of thousands of women" into "sexual slavery."

Abe didn't directly answer the question, but said he upholds the landmark 1993 apology by then-Chief Cabinet Secretary Yohei Kono.

"When it comes to the comfort women issue, my heart aches when I think about those people who were victimized by human trafficking, who were subjected to immeasurable pain and suffering beyond description," Abe told the audience through an interpreter.

"My feeling is no different from my predecessors," he said at the event, which the university streamed live online.

Abe was repeating his earlier remarks on comfort women almost word for word, apparently trying to carefully navigate the political minefield surrounding the issue.

When asked what steps Japan should take to reduce diplomatic tension in the Asia-Pacific region, Abe said Japan "has steadily tread on the path of a peace-loving nation" based on "deep remorse regarding World War II."

Abe has denied that Japanese government authorities or the military forcibly or directly recruited females for the brothels, apparently trying to emphasize that task was carried out by private-sector operators who mainly recruited females from the Korean Peninsula for Japan's wartime military brothels.

Speaking to the audience at Harvard, however, Abe did not bring up his pet discussion on how the females were brought to the "comfort stations."

Instead he stressed that he upholds the Kono statement, as has prime ministers who came before him.

Abe is set to address a joint session of the U.S. Congress in Washington on Wednesday. His speech there is likely to be provide a preview of the statement he will issue in August to mark the 70th anniversary of the end of World War II.

Many leaders around the world are keen to hear whether Abe's address to Congress will touch on Japan's wartime atrocities and colonial rule of the Korean Peninsula.

Abe is widely regarded as a historical revisionist who has tried to play down Japan's liability for its wartime misdeeds in the 1930s and '40s.

He and his aides appear to be trying to dispel or at least dilute this image while he is in the United States.

In the speech he delivered at Harvard before the question and answer session, Abe said he was determined to carry out structural reforms to make Japan's economy more productive.

He also emphasized that he is trying to improve the social status of women in Japan and encourage more of them to enter the workforce.

Abe pointed out that he tapped women for two of the top three executive posts of the ruling Liberal Democratic Party and is urging industry leaders to promote more women to management positions.

Hiring more women will improve the performance of those companies, Abe argued.

"I often say that had Lehman Brothers been Lehman Brothers and Sisters, they would still be around," Abe said, drawing laughter from the audience.