WASHINGTON -- The Obama administration will introduce its first statement calling for the United Nations' top human rights body to combat discrimination against gays and lesbians around the world, completing a U.S. reversal from years of ambiguity on the subject during the presidency of George W. Bush.

The U.S. declaration will be made Tuesday at the Geneva-based Human Rights Council and has the support of more than 80 countries. Although it is not in the form of binding resolution, the American push for U.N. action has helped win over a handful of new countries to the cause. A resolution could be brought to a vote later this year.

The issue of gay rights has polarized nations at the U.N. for years. And despite growing acceptance for homosexuality in Western nations and parts of Latin America, lawyers say there is still a gap in human rights treaties for the protection of gays against discrimination and mistreatment.

"We are very concerned that individuals continue to be killed, arrested and harassed around the world because of their sexual orientation or gender identity," said Suzanne Nossel, deputy assistant secretary of state for international organizations. "This statement sends a strong message from across the globe that such abuses should not be tolerated."

The U.S. document calls for nations to end any criminal punishments against lesbians, gays and bisexuals, and asks the global body to review how governments treat them in the U.N.'s human rights assessments. It acknowledges that "these are sensitive issues for many," but insists that people must be freed from discrimination because of their sexual orientation.

Nossel said the U.S. was proud to be taking a leading role in promoting the idea that gay rights are human rights - among the sharper foreign policy redirections that occurred after President Barack Obama took office.

Obama has stepped up the case for gay rights in recent months, winning a congressional vote to repeal the "don't ask, don't tell" ban on gays serving openly in the U.S. military and urging last weekend in a joint statement with the Brazilian president for the establishment of a special investigator to monitor respect for lesbians, gays, bisexuals and transgender individuals in the Western Hemisphere.

Under the Bush administration, the U.S. policy was markedly different. The administration didn't support a French resolution at the U.N. General Assembly in 2008 that addressed similar concerns, joining Russia, China, the Vatican and Islamic states in opposition. The U.S. explained its position at the time in technical terms, saying it was fearful of language that would infringe on the right of American states to legislate matters such as gay marriage.

In December, even the Obama administration held back from voting for a U.N. resolution condemning killings of vulnerable people around the world after specifically proposing an amendment to protect people based on their sexual orientation. At issue was a separate, arcane legal dispute over international human rights law.

U.N. General Assembly and Human Rights Council resolutions aren't legally binding; they reflect only the view of the majority of the world's nations.

But gay rights advocates say it is important to gather backers for statements, resolutions and other documents such as the one that will be presented Tuesday by the United States, even when their legal effect is null. Because gay rights are still hotly contested in many parts of Africa, the Middle East and elsewhere, establishing an ever larger coalition of countries can help create a legal norm such as those that exist for the protection of women, religious minorities, children and other vulnerable or marginalized groups.

Supporting the statement Tuesday will be newcomers such as Thailand, Rwanda, El Salvador, Honduras and the Dominican Republic.

The growing movement also highlights the gradual shift in the U.N.'s top human rights body, which has previously scorned the plight of gays and lesbians.

In 2003, the council's predecessor body, the Human Rights Commission held a heated dispute after a proposal made by Brazil and backed by European nations. Muslim countries balked, saying they couldn't accept any reference to the term "sexual orientation." Pakistan's ambassador went further, telling diplomats he preferred the term "sexual disorientation."