The Bush administration is intent this year on dramatically increasing the nation's stockpile of Tamiflu, a drug that can lessen the severity of bird flu, the company's president told lawmakers Tuesday.

George Abercrombie, president and CEO of Hoffmann-La Roche Inc., told a Senate panel that his company received a "letter of intent" from the Health and Human Services Department on Friday. The letter stated that purchases of Tamiflu for the U.S. stockpile this year may total enough to treat 46 million people, up from a previous estimate of 15 million.

The drug Tamiflu is considered one of the tools that the United States would use to reduce the impact of a pandemic, which occurs when an epidemic sweeps across the world.

Health officials are concerned that a bird flu virus primarily in Southeast Asia has the potential to become a pandemic if the virus mutates to the point that it can be spread from human to human.

Roche officials would not share the letter, but Abercrombie said the plan calls for the states ordering 28 million treatment courses and the federal government ordering 18 million.

Sen. Tom Harkin, D-Iowa, questioned whether some states had the resources to make such a commitment, particularly Louisiana and Mississippi, which are recovering from Hurricane Katrina. He said that protection from bird flu should not depend upon a state's ability to purchase medicine. He said he prefers national standards that would treat states equally.

Roche has filled the government's stockpiling orders to date, enough to treat about 5 million people. Abercrombie told the senators that global demand for Tamiflu means that the U.S. government must demonstrate a sustained commitment to buying the drug if it wants to ensure a supply will be available to it.