Prime Minister Shinzo Abe reiterated Thursday that there was no evidence of coercion by Japan's wartime government in using women across Asia as sex slaves.

"There has been debate over the question of whether there was coercion . . . but the fact is, there was no evidence to prove there was coercion as initially suggested," Abe told reporters Thursday. "That largely changes what constitutes the definition of coercion, and we have to take it from there."

Abe was responding to a recent U.S. congressional resolution calling for Japan's leader to "formally acknowledge, apologize and accept historical responsibility" for using "comfort women" -- the Japanese euphemism for thousands of women forced into sexual servitude for Japanese soldiers across Asia in the 1930s and 1940s.

A group of lawmakers in Abe's Liberal Democratic Party are also moving to downgrade Japan's 1993 statement by then Chief Cabinet Secretary Yohei Kono that Japan's wartime military was directly and indirectly involved in setting up and operating brothels and recruited women with coercion sometimes.

Japanese leaders have repeatedly apologized, including former Prime Minister Junichiro Koizumi, who said in 2001 that he felt sincere remorse over the comfort women's "immeasurable and painful experiences."

Since taking office in September, Abe himself has pledged to honor the 1993 statement by Kono. However, he told a Diet session in October that there was no evidence to prove there was coercion "in a narrow sense" in the way the women were brought to the frontline brothels.

But many LDP members who seek to whitewash Japan's wartime atrocities have long attacked the 1993 statement by Kono, who is now speaker of the lower house.

Three women who said they were gang raped and tortured at the hands of Japanese soldiers during the war and endured a lifetime of mental and physical scars testified in February in written statements at a hearing of the U.S. House Subcommittee on Asia, the Pacific and the Global Environment.