Secretary of State Hillary Clinton and former presidents Bill Clinton and George W. Bush are among the politicians expected to attend the 19th International AIDS Conference taking place at the Washington Convention Center next week.

President Barack Obama will record a brief video message for attendees.

“The president will not be speaking at the conference,” White House spokesman Shin Inouye told gay weekly the Washington Blade. “He will provide a brief video message to welcome conference attendees from around the world to Washington.”

This is the first time that the United States has hosted the conference since 1990 due to a travel ban which restricted people living with HIV from entering the country. In 2009, President Obama signed legislation which ended the 22-year ban.

Senior Obama Administration officials – in addition to Hillary Clinton – participating in the conference include Secretary of Health and Human Services Kathleen Sebelius; U.S. Global AIDS Coordinator Ambassador Eric Goosby; Director of the White House Office of National AIDS Policy Grant Colfax; and Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, NIH.

Obama's decision not to attend was met with varying reactions from HIV/AIDS advocates.

“While we are disappointed that President Obama will be unable to address the International AIDS Conference in person, his decision to address attendees via video demonstrates the importance he places on AIDS 2012 and HIV,” said Brian Hujdich, executive director of HealthHIV. “As the first president to set a comprehensive National HIV/AIDS Strategy and pass meaningful healthcare reform, his commitment to addressing HIV prevention care and treatment is strongly demonstrated.”

Tom Myers, chief of public affairs for the AIDS Healthcare Foundation, expressed concern over the president's decision.

“In the 20-odd year history of this conference, it is virtually obligatory for the head of state of the host nation to address the conference at its opening,” Myers said last week.