U.S. President George W. Bush walks across the South Lawn to board Marine One at the White House in Washington on July 25, 2008. President Bush is going to a private luncheon in Peoria, Illinois. (UPI Photo/Alexis C. Glenn)

In his weekly radio address, Bush said he will sign legislation passed this week by Congress expanding the Emergency Plan for AIDS Relief, also known as PEPFAR.

"PEPFAR is the largest international health initiative dedicated to fighting a single disease in history," he said. "And it is a testament to the extraordinary compassion and generosity of the American people."

Bush said 1.7 million people with AIDS in sub-Saharan Africa are receiving anti-retroviral treatment through the program -- up from 50,000 when the program began more than five years ago.

The president said similar aid programs help promote freedom by "combating hopelessness."

"This is because the only way that the enemies of freedom can attract new recruits to their dark ideology is to exploit distress and despair," he said.

"With all these steps, we're helping defeat the forces of violent extremism by offering a more hopeful vision of freedom," he said. "And as this vision takes hold in more nations around the world, America will be safer here at home."