The head of the United States' fight against the global AIDS epidemic is urging leaders in AIDS-affected countries to speak out about the disease. Randall Tobias took a conciliatory tone, despite criticism this week of U.S. AIDS policy.

Ambassador Randall Tobias says when the mayor of Ethiopia's capital was tested for HIV, it encouraged others in his community to get tested. Mr. Tobias called on other officials around the world to step forward to reduce the stigma surrounding AIDS and HIV, the virus that causes it.

About 50 protesters held up Mr. Tobias' speech Wednesday. They heckled him when he said President Bush's AIDS relief plan allows generic drugs only if they pass U.S. quality tests.

"America will have one health standard for its citizens and cannot have a lower standard for those who are suffering elsewhere," said Ambassador Tobias.

Critics say the president's plan undermines a World Health Organization drug program.

Despite the hecklers, and criticism on Tuesday from France about U.S. AIDS policy, Mr. Tobias took a conciliatory tone in his speech. He warned that unity is essential to fighting AIDS.

"HIV-AIDS is the real enemy," he said. "The denial, and stigma, and complacency that fuel HIV-AIDS, these, too, are the real enemies. And it is a moral imperative that we direct our energies at these real enemies and not at one another."

Mr. Tobias is the United States' global coordinator for AIDS policy, and is leading the U.S. delegation at the International AIDS Conference this week in Bangkok.

The Bush administration favors a three-tiered prevention approach that first stresses sexual abstinence and faithfulness, and then condom use. Many AIDS experts and activists say the administration places too much emphasis on abstinence and not enough on condoms.

"There is no one right answer to preventing the spread of this pandemic," said Randall Tobias. "And those who want to simplify the solution to just one method - any one method - simply do not understand the complexity of the problem."

He also reiterated the Bush administration's support for faith-based AIDS programs, which he said often go into remote regions and slums where other agencies will not go.

The U.S. government is the largest donor in the fight against AIDS and the Bush administration plan also includes providing more medical workers and researchers around the world to contain the disease.