WASHINGTON -- As President Barack Obama celebrated his legacy on women's rights at the United State of Women White House summit on Tuesday, reproductive and human rights advocates gathered outside the event to demand his action on abortion access for women raped in conflict .

Several groups, including Reproaction, the Center for Health and Gender Equity and Amnesty International USA, are calling attention to the president's failure to change the Helms Amendment, a longstanding policy that blocks United States foreign aid money from being used for safe abortion care for women raped in conflict. Obama could use executive action to add exceptions to the anti-abortion law that would permit funding in the cases of rape, incest and a woman's life being in danger. He hasn't done so, despite mounting pressure from women's rights advocates, Democrats in Congress and the United Nations .

As long as President Obama continues to walk away from women raped in conflict, his legacy on gender equality is incomplete, CHANGE president Serra Sippel said. To remain silent and fail to act is unconscionable, deadly and damages his legacy.

The advocates also placed a full-page ad in The Washington Post on Tuesday, criticizing the president for failing to act on Helms and for neglecting to address abortion rights directly at his summit.

"We have grown weary of years of excuses and silence," the ad reads. "Women would benefit greatly if President Obama took leadership to break barriers to abortion."

Until the president reconsiders his stand on foreign aid for abortion, especially for women who have been raped or whose lives are in danger, humanitarian aid groups won't be able to use U.S. donations to provide the full range of medical options to pregnant women and girls who have been rescued from groups like the self-described Islamic State and Boko Haram.

The schedule for the White House event doesn't include any speakers or discussions specifically addressing abortion , but there is a session about unplanned pregnancy. The summit is also supposed to cover such topics as violence against women and women's economic empowerment, educational opportunity and health.

The White House did not immediately respond to a request for comment.

Presumptive Democratic nominee Hillary Clinton said that if Obama doesn't change Helms and she wins November's general election, she will reinterpret the abortion restriction to have exceptions for rape, incest and saving the life of the mother.

Yes, Hillary Clinton would fix the Helms Amendment, a campaign spokeswoman told The Huffington Post. She believes we need to take a close look [at] this. The systematic use of rape as a tool of war is a tactic of vicious militias and insurgent and terrorist groups around the world. She saw first hand as Secretary of State the suffering of survivors of sexual violence in armed conflict during her visit to Goma [in the Democratic Republic of Congo] in 2009. She believes we should help women who have been raped in conflict get the care that they need.