The U.S. State Department lowered its travel warning on South Korea to "Reconsider Travel" on Thursday.

"Reconsider Travel" is level three on the State Department's four-tiered travel advisory system.

The United States placed a "Do Not Travel" advisory, its highest warning, on the city of Daegu on February 29, while leaving the rest of the country at "Reconsider Travel."

On March 19, however, the United States placed a "Do Not Travel" advisory on the entire world.

The State Department lifted this blanket warning on Thursday and restored the existing system of determining travel warnings on a per-nation basis.