The United States will declare the swine flu outbreak a public health emergency, Homeland Security Director Janet Napolitano said today.

Speaking at a White House press briefing, Napolitano said the declaration is not as severe it sounds.

"This is standard operating procedure and allows us to free up federal, state and local agencies and their resources," Napolitano said.

The declaration does not necessarily convey the authority to initiate quarantines.

"We're nowhere near that kind of decision," Napolitano said.

Also at the briefing, the Director of the Center for Disease Control, Richard Besser, warned that there will likely be more cases of the swine flu detected in the U.S., adding those cases will grow more severe.