Japanese Prime Minister Shinzo Abe will stand by Japan's apology for forcing Asian women to have sex with Japanese troops decades ago, an aide said Sunday, following Asian nations' outcry over Abe's recent denial of coercion.

"Though there are many definitions of coercion. Prime Minister Abe has said ... that he will stand by the Kono statement," said Hiroshige Seko, special adviser in charge of Abe's public relations.

Seko was referring to a statement issued by then-Chief Cabinet Secretary Yohei Kono, apologizing to victims of sex slavery.

Kono's 1993 statement also acknowledged that many women were forced into prostitution, and that the military government was involved in some cases.

"He (Abe) has not denied the statement," Seko said on a TV Asahi talk show. He did not attempt to explain the apparent discrepancies between the statement and Abe's denial that coercion was involved.

Abe sparked international outrage last week by saying there was no evidence to prove that women were forced into military brothels across Asia.

"The fact is, there is no evidence to prove there was coercion," Abe told reporters on Thursday.

South Korea later lodged an official protest, accusing the leader of "glossing over the historical truth." Rights activists in the Philippines also slammed Abe for labeling the slaves as common prostitutes.

Historians say that about 200,000 women, mostly from Korea and China, served in Japanese military brothels throughout Asia in the 1930s and '40s. Accounts of abuse by the military have been backed up by witnesses, and even former Japanese soldiers.

But prominent Japanese scholars and politicians routinely deny direct military involvement or the use of force in rounding up the women, blaming private contractors for any abuses.

Kono's apology did not meet demands by former sex slaves that it be approved by Parliament.

The government followed Kono's statement in 1995 by setting up a fund to meet victims' compensation demands, but the fund was based on private donations _ rather than government money _ and has been attacked as a government ruse to avoid owning up to the abuse.

The fund is due to expire on March 31.